I bought one of these for £150 from Maplin in June 2012, because I liked the idea of tablet computers, but didn't feel like risking £450 on something that I might end up not using very often. Here are my first impressions.
The case feels reasonably solid.
Screen: clear and sharp, but it has a very narrow optimum viewing angle. This is especially evident with video.
It takes about 30 seconds to start from fully off, but wakes up from sleep in one or two. Just put it to sleep when you're not using it.
The battery lasts about two hours from a full charge browsing the web. Recharging takes longer (surprise!), and it seems to spend a long time on 99% charge before it gets to 100%. I usually leave it on charge overnight, and have to recharge it during the day at weekends.
The on-screen keyboard is responsive and well laid out, but a 16:9 screen is not ideal for writing - in landscape mode the keyboard takes up half of the screen, but if you turn it to portrait, the keys are too small for my hands.
This review was mostly written on the tablet, using Text Edit from Arnova's app store.
The built-in speaker is very small, and struggles with anything more than clicks and bleeps. The tablet has a standard headphone socket, and the sound from this was fine.
Software is a big problem - the real Android Market does not recognise this tablet. Arnova have their own pet App Store, but there's a lot missing - Kindle, for example. You can fix this by installing third-party firmware, but this not a thing to be done lightly. Google "arnova 10b g3 firmware" if you want to have a go.
EDIT: see the first comment for a different method.
Video: the tablet comes with a demo CGI animation in .avi format. This played smoothly on the video app.
Music: I bought and downloaded a song from Amazon. The music player found it automatically, and it sounded OK on headphones.
Camera: probably acceptable as a webcam.
It only has 4GB of internal storage, but that's enough if you're using the tablet for web browsing and email. It has a slot for a micro SD card if you need more space.
I've been a bit cool about it so far, so do I regret buying it? For £150, absolutely not. I mostly used my desktop PC for browsing and email, and I've hardly touched it since I bought the tablet. The default browser Just Works on nearly every website, and the alternative browser Dolphin (free from the app store) is also very good. The 10 inch screen means that web sites can display in desktop format with no problems. Some sites (e.g. BBC, Daily Telegraph) will automatically render themselves in mobile versions which look better with the screen in Portrait mode, but turning the tablet round is no hardship.
I've rated it at 4 stars - if it had better battery life and no-fiddling-around access to the real Android Market, the score would have been 5.
EDIT: after I had had the tablet for about three weeks, the touch screen stopped responding, and the tablet went into a reboot loop. So I took it back to the shop for a refund. I was told that this was an unusual fault for Arnova gear (plug problems are more common, IIRC). I was offered a replacement, but decided to try my luck with an A1CS brand tablet from Amazon, which have a similar price and spec, but better out-of-the-box Android Market access.
I have not changed the review score, because I have no idea how common of rare this hardware fault is.