Nothing to look out for. It's a beautifully made and great sounding head. It has one of the few 'enhance' type controls in the industry that I find useful and musical through much of its range, and the Timbre control is very powerful, and its impact will be obvious. Most don't vary that control more than a little bit of center either way.
I guess the only thing that might be a touch confusing is the 'switch'. The switch has minimal impact until the amp is cranked and pushed quite a bit. To my ear, in SS mode, the amp will stay very even and constant sounding over its entire range, whereas in 'tube emulation mode' it will mimic a little bit of that tube warmth and 'sag' when pushed. The amp stays very clean and quick in both modes, but just fattens up a touch in tube emulation mode.
Finally, remember that the limiter is more of a 'speaker protection' type circuit versus a full function limiter/compressor and should be used sparingly... i.e., so that the limiter kicks in only at your hardest played low notes. Another fun fact, you will notice that the amp will sound slightly different with the input limiter switch 'on' (a little fatter and fuller), even when the limiter is not engaging. Many Thunderfunk users keep the limiter switch engaged at all times, and just turn the gain down a touch if they don't want the limiting to engage.
Whoo... OK, maybe more to look out for than I originally thought. It's a great piece of gear... warm, a little bit vintage sounding, but tight and quick. It's beautifully voiced to punch through a mix.
Enjoy, and put up a review when you have some playing time with it!
K
Edit: From you profile and influences, your are going to LOVE this rig. The TF/Accugroove is a very wonderful 'updated vintage' tone... warm and fat, but quick and punchy all at the same time. The three way design of the AC cabs, with those nice paper cone mids and tweeter, sound more like a really good one way cab, if that makes sense. Old school, but with wonderful articulation and clarity. Not totally my thing personally, but I've heard a few of these rigs out front, and man, they sound good for that tone goal!