IMO get a very high CFM Fan. Like a Silverstone 110 CFM 120mm fan (i chose this because it comes with a fan controller). With a fan controller so you can have varying degrees of cooling. If you want it quiet put it on very low. If you want it at like 25C then put it at max lol.
Doesn't really matter what model you get, so long as it meets the cfm and noise level that you can tolerate.
Most modern motherboards have a QFan option within the BIOS, that can regulate a PWM Fan to different speed settings base on temp. Just make sure your Scythe is a PWM, or else you'd have to get some third party fan controller to control the fan speed.
I am using a Scythe SFF21F (63 cfm) with my TRUE. It's cooling a Q6600 OC'd to 3.6 GHz in an Antec 900 case. It's oriented vertically to take advantage of the 20 cm fan on top. (Hot air wants to rise; why fight physics.) I am letting the motherboard control the fan.
The machine work on the base was not particularly good. I hand lapped to take out the machine marks and to even out an offcenter bulge. It also exposed the copper core.
Currently, the Xigmatek s1283 is attracting a lot of attention. Performance is very, very close to the TRUE. And it's about half the price of a TRUE and fan.