I have had a bit of experience with tweaking RST's in the past, We used water injection to keep the charge temp down and found the Pace IC had a bit of an advantage as it didn't block the rad and could handle the Extra boost. We did have a problem with the early ones Splitting but i think the welds have got allot better since my Tuning days.

I have seen FMIC's SMIC's and charge coolers used on RST's and to be honest they all had there own faults.

If its for Road use only the Charge cooler wins hands down but is Crap for track days. There designed for burst runs not sustained WOT.

From first hand experience i wouldn't get a FMIC because the seriously hinder the air flow through the rad. I am not 100% sure why it was designed like that? I'm guessing they put the IC in ft of the rad because its the only place they could fit an IC of that size? maybe they where also thinking the lower inlet temp would compensate for the higher water temp?