So complicated!
Just looking at the graphs it doesn't look very competitive against other cooling solutions, but the price makes it look more attractive.
It is a situation that cries out desperately for a scatter plot, with performance on one axis and price on the other.
I'd do it but I'm too lazy, and I don't care enough.

EDIT: Fine, I do have too much time on my hands.
http://imageshack.us/a/img404/8472/plotfinal.jpg
S1155 HSF only - X-axis = Price (US$ gathered from various US online retailers, YMMV) and Y-axis = Delta T (from article)

Observations:

• As we can see Intel OEM HSF is both cheap and ineffective, so it is at the Top-Left of the plot.
• The Thermaltake Water 2.0 Pro is most expensive and is on the far-Right. We can note that it is significantly more expensive than the other AIO water-coolers from Corsair and Antec, yet performs no better.
• The ideal HSF for price/performance would be one that is to the Bottom-Left. The best HSF that matches the ideal profile is the Arctic Cooling i30 which is both cheap and effective, if at the expense of some noise.
• The Gelid Tranquillo R2 is not as good as the i30, but it is slightly cheaper and quieter, while out performing the Gelid GX-7 and the Thermolab Trinity. I cannot see why you would buy either of the last two.
• The Phantecks and the two Be Quiet! HSF are very expensive air coolers, and purchasing either of the Be Quiet!s would be an ask, especially the Pro 2 where both the Corsair H80 and Antec 920 are cheaper. The Phantecks is cheaper, but there is the Zalman CNPS14x that neatly straddles the Phantecks' high/low performance for $23 less.

Personal Decision:

• If I was on a budget and I wanted quiet I'd go Gelid Tranquillo, and if I wanted performance the Arctic Cooling i30.
• If my budget could stretch a bit further I would go with the Zalman CNPS14x.
• If I was going to spend serious coin on cooling I would probably go with the Corsair H80.

Oh wow a rather decent cooler from Zalman? They've been completely lost with this stuff for YEARS... Good to see them back.

I don't get it - the thing is HUGE and ridiculously heavy yet it doesn't do a very good job. I guess put a better fan in it and it could be a major competitor.

fitting the spanner between the heatsinks and RAM on our motherboards proved to be very difficult for some bolts.

wouldn't you just remove the RAM for this??

a bigger complaint would be the positioning of VRM components by cooler mounts making fitting a pain