I had (still have it in a box..) a Volcano 7 (not 7+) and I had it on my XP1800+ @ XP2000+ speeds. I cut off the thermal sensor so that the fan would run full speed all the time (really loud). It worked, got ~35C temps at full speed, but was really loud. I just recently put it on my fan bus (switches, not a rheobus) so I can have High/Low/Off. At low, I was getting close to 50C temps after not a long time (all temps are full processor load--Folding@Home) with it at low. Even more recently, I bought an SLK-800 from my friend, and now I get ~40C with the low fan setting (very quiet from what I'm used to) and ~31C on full.
Get a ThermalRight, or else you'll get frustrated with the ThermalTake after a while and will want to get a ThermalRight anyways