Whats a nice boost controller to get?

I fancy the blitz I-color one but the price is a bit steep.

What exactly does the boost controler need to suit my car?

Im in the process of chaging to a GT28RS and think i need one after.

Spec is :-

Motorsport manifold
Milltek Gt28 Downpipe
GT28RS Turbo
Cat back
Denso ITV's
Panel filter
Bluefin
Motorsport HT Leads.

Think thats it??

Thank you for your time lads.