So here's my review of the Teclast C290, recovered from the old MP4Nation forums via Google, edited, and reorganized a bit:
Okay, I got my Teclast C290 courtesy of an MP4Nation contest. THANKS! There's a lot of criticism below, but let me make it clear that despite this I'm very pleased with it overall, and it will definitely tide me over for quite a while.
The Box and its Contents
The packaging had a sophisticated look to it, which would make it a nice surprise to unwrap as a present. It certainly didn't have a "cheap iPod" feel to it. It came with some functional, but low quality, in-ear headphones. There was a USB cord, a nice little polyester (?) drawstring bag which fits it nicely as well as a leather wriststrap, all of which are appreciated. There's also a manual which is entirely in an Asian language, so it's quite useless to me, although I would like to look up a few things about the interface.
First Impressions
The player itself is pretty: glossy black, with touch buttons which light up red when you use them, but are otherwise invisible when not in use. I've never used another player, so I have nothing to compare it to, but my first impression was that the screen was beautiful. Bright, crisp, easily seen in a fully-lighted kitchen or in the dark.
Photo and Video Function
The pre-loaded photos and videos look great, and the latter play smoothly. As one of the things I was looking for in a player was to use it as a portable photo-album, I'm overjoyed with that feature. JPEGs have to be below a certain resolution to display, but resizing is a no-brainer.
The Interface
The interface is non-intuitive, but I figured it out after a few minutes and the buttons make sense once you get used to them. There are inaccessible folders shown on screen at times, which, although I figured it out pretty quickly, someone who isn't good with computers would probably find confusing (NOT a good present for grandma). There's a forward arrow and a back arrow, which are used to navigate around the menus and to fast forward songs. Then there's an M key which functions sort of like the enter key in that you use it to make selections. There's a V which is used to back up a level to a higher menu level and also used to adjust the volume. There's a play/pause button. Also, depending on what function you're in, the keys have different uses, which just have to be figured out by experimentation as the manual cannot be deciphered. For example: pressing the M & V buttons simultaneously with a file selected gives you the option to delete that file. Finally, if your music files are too deeply nested in folders within folders, the player cannot access them so make sure when transferring your files to just transfer the files themselves and not bury them within levels of folders. The only really annoying problem with the interface is that the touch buttons are sometimes not sensitive enough. They're fine most of the time, but on occasion, it takes multiple touches to get them to respond. The touch buttons especially don't like to respond to calloused fingertips.
The G-sensor
The G-sensor is MOSTLY useless, as I expected. Certainly you don't want to use it to change songs or move around a menu. HOWEVER, you can use it as a directional control in game play by simply tilting the player in the direction you want to go. A bit like a joy stick, really. In that sense, it's VERY cool. As far as the G-sensor accidentally going off, simply picking up and manipulating the player did not do so and there's the option to turn off the G-sensor available in the setup menus.
Games
So loaded on the player is a gaming platform with one preloaded fighter plane game. The game prompts are in Asian script which is a pain, but the Asian version of the game can be replaced with the English version included in the Rockchip game bundle available on the internet. Otherwise, it was a beautiful game for such a small machine. The game IS addicting--I love using the G-sensor to control the game. This works by tilting the player in the direction you want the fighter plane to go. It's intuitive and MUCH easier than using the touch buttons. It does drain the battery quickly. I was able to get the other rock chip games installed on my player after downloading them from the internet. Snake works nicely with the use of the G-sensor to control the snake. Tilt the player in the direction you want to move the snake and it moves that way. Tank seems to work well, also with the G-sensor tilt as a directional control, but I found it too difficult a game for me, so I didn't play with it much. Tetris and the Pirates game don't work well enough to be functional. The controls work inconsistently for those two games. And I replaced the Chinese version of the fighter plane game which runs really well, with the English version which also runs well. The main flaw with the game platform is that I'm able to switch between the multiple games, but I can't exit the game platform without shutting down the player.
Music
It does just what I'd expect it to do. Easy to navigate within or between songs. The music sounds good. One of the handful of preloaded songs is even kind of cool, combining pop stylings with an Asian scale. Audio quality is great. I hooked it up to the external speakers that I use with my laptop and I swear that the sound quality was better than that which my laptop produces. Probably the biggest problem with the player is the following: when listening to music, the screen shuts off after a bit. This is important and intended, of course, to save battery time. However, the machine is a bit slow to wake up from this and is usually unresponsive for a few moments, up to 10 seconds or so at times. Not a big deal, but occasionally I want to skip a song or change the volume and have to wait for it.
Radio
The radio is nice. It allows you to save several preset stations and also to scan for stations which it has good reception for. The only problem with the latter is that it has higher standards than I do. I might listen to a station with worse reception than it might pick up on a scan. Still, if you really want to listen to a station with substandard reception, you can manually select the station. It also only seems to have FM stations, as far as I can tell.
Voice Recorder
The voice recorder doesn't work at all on my unit. I took the common sense approach and tried every button to make it record, including the play/pause button. None worked. The only other possible thing to try would be some combination of buttons. I actually don't care that much about the record function, as my phone has a voice memo function that works should I ever want one while I'm travelling.
Odometer
My initial tests of the odometer didn't seem to work very well. It miscounted steps.
Conclusion
Overall, it does what I want it to and looks classy at the same time, so I'm happy! Well, and I got it free.

In summary, great screen quality, G-sensor is great for game play, but not for interface navigation, great sound quality. The two biggest flaws are its occasionally undersensitive touch buttons and the slow-to-wake-up-screen when it goes into standby.