Been meaning to update this. I bought the Laney VC30 for 320€. I'm still getting used to it, but the sound is quite nice. Turning it up past 0.5 (as in, half of one!) is not possible in my apartment, so I've only had it cranked once at band practice so far. Unfortunately there's a problem with the reverb, if I turn it up past 2 or so and the amp gets loud, I start getting unpredictable and incredibly loud bursts of distorted crackling. According to some things I've read, a few people have a similar problem which ended up being caused by nothing more serious than a loose cable from the tank to the board. Next time I'm at practice I'll take a look at it.
I considered going the 15 watt route, and also the DIY route. The last thing I wanted was an amp that was going to break up when I wanted a clean tone, so I went with the 30 to be on the safe side. I am somewhat handy with a soldering iron, but I've never taken on a project as large as an amp (only done pedals and some circuit bending so far), and probably don't have the time to dedicate to such a large project at the moment. If I can get this reverb issue sorted, I think I'll have made a good purchase for the price.