Pro/Forums - Rack mounted cooler

Okay - I'm currently going through a slow transition of rack-mounting my kit ( my main rig is a coolermaster 410) and was just finishing a pedistal-type external cooler. I've scrapped that though and because I'm planning on cooling a rack kit thought I would make a rack-mounted cooler. I have a few ideas on format and such but have been struggling with one major choice. Maybe everyone can give a helping hand.

The first option I see is getting a big rad (such as aqua's 1800) and putting say 15 x 120mm fans on it with a huge fan bus on the front of the case.

The second option i saw as that if this is a separate unit with more flexibility/etc. then how about using a tec and heat exchanger? This would give a much hotter effect on one site but that could be cooled with a heatsink and say 3 x 120mm fans.

Any thoughts?

and just to clarify the purpose of this - I want to be able to cool multiple units at or just above room temp - I'm not all that interesting in extreme - extreme cooling.

Cheers,