I'm going with a Budda this weekend. Local GC has a SD30 combo for purchase, but I want a head instead. My question is, do I what makes more sense for my application. If I use the head on top of a 4x12 and mic the amp, is 30 watts too much? I'm leaning toward the 30 since we may play shows that we don't mic in slightly larger rooms and I want the head room and power. I've read that the 30 watt is not much more than the 18, but that it has a little more headroom and thump, which is what I would want. Just wanting your thoughts and opinions. Also, I could purchase the SD30 combo this weekend. How many of you put it on top of another 2x12? What ohms does it run normally and how would I run it with a 16 ohm mono 2x12 cab?