The sound is very good and the engine is DEEP, you can create almost any sound with it if you have the skills. Though you need to somewhat know what you're doing, it's not really a happy accidents -type of an interface.
The keyboard is probably the best I've ever played, including some much more expensive instruments. Mod and pitch wheels could be better, they are thin and look and feel cheap.
The master volume encoder started to jump on it's own now and then after couple of months of use. It doesn't do it often enough to send it back for warranty repairs, but it's a bit annoying. It seems that Waldorf still uses bad quality encoders with the Blofeld despite it's been a well known problem for years. I'm thankful for Thomann's 3 year warranty.
The firmware is bug free since 2014 as far as I can tell, so no complaints about that.
Overall it's a really good synth for the price.