I recently traded for an RS212 and was really surprised with the clarity, low end and tone compared to my Ampeg PR410hlf. My daughter, who recently started playing bass, said it's like HD compared to SD. Well said! After doing some more research, most reviewers were saying if you like 1, you'll love 2. Wow were they right! I've been stalking a used RS212 at the local GC and my wife was able to score a really good out the door deal. Way better than I could get the night before. I know, imagine that.
I really like the vertical stacking aspect so turning up to hear will be a lot easier. Our guitar player liked the idea so much he is going to do the same with a pair of 2x12 cabs he has. I'm currently using a Hartke LH1000 but might start looking for an RH450 or other small factor head. As soon as schedules allow I'll have some bass player friends with Markbass, Orange and SWR heads over for a night of loud bass and beer. We'll see what "sounds" the best and annoy the neighbors.
Remember, it's all for science kids.