I run a pair of Quicksilver Horn Monos with my Klipsch la Scalas (104db) - at only 25w per side, I can still drive the room to unsafe levels without coming apart soundwise. Metal, prog, 70's hard rock, space rock, classic dub, avant garde electronica, in about that order. A tube amp is most definitely worth considering. With tube amps, one of the benefits is the ability to tweak the sound through your tube selection. In either case (tube or solid state), I would look for an amp with a neutral to soft presentation, which would be beneficial for the less-well recorded material, as an overly forward or crisp amp can sound harsh with sensitive speakers and the often compressed source material we listen to.
For solid state, perhaps one of the new Pass Labs amps (X.5 series, or the new Aleph J) might be of interest. I've only heard the older ones (Aleph 3 and Aleph 30), and liked them quite a bit with my setup.
I imagine you can produce a bit more bass with those speakers than with my setup - you should check the impedance curve of your speakers to see if they are a difficult load in any frequency range. If they aren't a difficult load, you could consider some smaller to intermediate wattage tube amps (but I wouldn't go below 25w), or some smaller wattage class A amps (Pass Aleph J comes to mind.) If they are a difficult load, or want more bass/slam, a higher-power push-pull tube amp would be a nice fit. My only experience with higher-powered tube amps is with the Rogue M120s (120w, 4 KT88 or similar per side) which produced enough power and slam to satisfy all my wildest metal listening sessions (at any volume, and then some). They're well below your pricerange, and there are more refined amps to be sure, but as far as power and suitability to the source material, it does go to answer your question (from my viewpoint) that "yes", a tube amp is well worth considering for this type of music and setup.
