I've got one and like it, though I'll admit I haven't really utilized it fully extensively. Replaced a Athlon II X2 250. My stock volts were outrageous (1.4V, 1.45V w/ Turbo). I've since deactivated turbo and undervolted it across the the board (1.25V at 2.8GHz, 0.75V at 800MHz) so that it now idles near my X2 250's idle wattage (within a few watts) and maxes out near 48C in LinX. In the little multithreaded rendering I do, it was a tremendous improvement. In most other areas the improvement was much smaller.
I've just recently built a 1055t system with 8 Gb ddr3 1600 RAM on a 785G chipset for a friend. I found it to be stable up to 3.8 GHz with little V bump, could have probably pushed it more if I had wanted. It didn't get overly hot with an arctic cooler freezer pro 7, but did start to approach the magical 60C mark under prime95. I didn't leave it at this setting for too long for a couple reasons.
One, I didn't want to burn up his board. It didn't have any mosfet sinks or bells and whistles. Plus, it only had 4 phase power regulation.
Second, he didn't want it overclocked. I actually ended up undervolting the system quite a bit for him. I can't remember exactly, but as EXT said above, the defaults are rather high! I believe I brought the core voltage down to around 1.25-1.30 volts as well, and the temps stayed below 50 during my prime testing. I didn't need to add any voltage to the NB to make all 8 GB of ram work at 1600 MHz either.
The best part is, with these specs, I was able to build a system that had 2 Hd's 1055t, 785g (I know, but it wasn't for gaming), 8 GB RAM, some extras, and it idled at about 80 watts! (tested with a 300 W PSU and kill-a-watt).
I can't remember the load figures, but it wasn't bad at all. He ended up getting a pretty bad a$$ workstation for less than anything he could buy from an OEM company.
The speed is usually a relative figure. I have a 955BE @ 3.8 GHz so I was able to do a fair comparison between the two machines. I have a better graphics system, but as far as things that required the CPU goes, I couldn't tell much difference. I don't have any programs that would tax a hexacore any more than they will tax my quad. I'm sure if it were the case that I was running massively threaded apps as he does it would make things a little more noticeable.
However, we are talking about two machines, identical architecture, identical clock speed, equal ram, ect... Fast is fast no matter how you gauge it!