Intercooler upgrade Q's
 

What is the advantage(if any) of upgrading the intercooler on a car that will have the following mods:

APS turbo-back
HKS 272's
Buschur ported TME turbo
APS or HKS rs intake
Buschur ported and coated exhaust and o2 housings
walbro pump& ARP headstuds
Custom turbotrix tune.

I probably wont exceed the cooling capacity of the stock intercooler with the above, but is there anything to be gained in terms of midrange power, reduced spool-up time etc. in upgrading to a larger intercooler?

I am sure that people will chime in that it is worth 20HP, but I really wonder. This is the one item where I just don't trust the dyno. The conditions on the Dyno just don't replicate real world driving. The only proof for me would be lower ET's with just the intercooler upgrade.