Not THAT bad. Consider that I, myself, am compulsive-obsessive about "best" air-cooling. I had order the TR-Ultra-120 (original) for this system, getting ready to make the installation when the news about the "Extreme" version appeared. Then there was the news about the "Extreme's" slightly convex shape, and I realized I'd have to lap the heatsink base. Then I found a reseller selling "custom-lapped" Extremes. I paid the extra $30 to save myself the trouble.
Reviews often mask "performance" in two ways. They either don't show comparisons with other coolers, or they exclude the best coolers from the comparison. Beyond that, they usually show the evaluation with a controlled room-ambient temperature, the idle temperature, a load temperature, and a processor spec. The processor spec, in turn, gives a TDP or thermal-design-power in thermal watts. They may compare the same processor at different over-clock settings, which then implies higher TDP's for those over-clocks.
But they often do not show "thermal resistance." TR folds into a single number the information about idle and load temperature values with the TDP, and excludes a need to adjust for room-ambient, because it measures a change in temperature given a certain processor thermal wattage. It is THE accurate measure of heatsink effectiveness and performance, provided that a range of fan-speeds that may change thermal resistance are also reported.
Look for reviews on the Arctic Cooling 7 Pro, see if you can assess the thermal wattage of the test-configuration, make a note of the room-ambient test-condition, and see if you can't compare the temperature data with the data shown in the Anandtech review comparisons (some 20 coolers) with the ThermalRight Ultra-120-Extreme (May 5, 07) and the Ultima 90 (August-something, 07). That'll give you a better idea . . . .