Despite good cases being available for a bit more (a never-ending game by the way), the 300 does represent good value for money, though it was a lot better before the recession hit, I'm sure it was around £35 mark or even less.
Because they're cheap, they're also quite simple and easy to mod, coupled with the fact that it's not a big deal if you cut it in half by accident or some other dremel-related mishap.
There have been a fair few threads (not many recently) with 300's, though OP, I recommend doing a search of the 'new builds gallery' thread (I think that's right) and you'll find many, and some inspiration to get your tools and paint out.