Take it from me. I am going through the process right now. I was like you and wanted to go ahead and do the cobb stages while saving for a V7 later down the road. Well now I have a blown engine and am getting ready to get the JDM Engine. I would of been much better off if I had done the swap to begin with.
I blew my engine after going to cobb stage 2.5. I only had it installed for a day before it made a nasty boost spike and killed a ring/valve. Luckly I can sell the vf30, injectors, accessport, and fuel pump for a good amount because they are practically brand new.
I got a quote from kingpin... The engine is 4500, reflash is 550, and labor is 75 an hour. It usually takes 8-10 hours. Then they sell your engine for you and take 10% of that and you get they rest. Normally you get 1800-2000 out of your engine.
So for around 3 large you have a JDM STi V7 installed, tuned, and ready to roll!
Do it right the first time!