Unreliable big power RST's is a bit of a myth. If they are built properly they aren't much trouble at all. Mine was in use as a daily driver until July last year. SCC built it and it's been putting 250bhp out with only very minor issues along the way.

180-190bhp is a piece of p1ss mate. I would start with:-

Magnex, Mongoose or Scorpion exhaust
K&N panel in drilled airbox
Chip
-31 actuator
Intercooler.
A decent setup

This should have you pretty close to where you want to be. The key to the reliabilty is how good the engine is to start with. There isn't much point in tuning a 130,000 mile car as it's only a matter of time until it goes bang.