Not really mate, sunnys kit was just a turbo, manifold adaptor with manifold, intercooler and piping, with boost gauge and controller. You could pick all that stuff up for around £350! You don't have to go for the rod bolts, as my power graph shows power dropping off after 5000rpm, so to get max accelleration, you'd change around 6000, that's why my 1/4 mile time isn't as good as it could be. Rod bolts really only need to be changed if you increase rev limit. So I don't feel I really needed them.
Even if you did change rod bolts, it's only an hours job, just drop the sump off, & the baffle plate, then the oil pick up, & the rod bolts are just there to swap out! You don't need to lower compression if you only want to run low boost, I just did it because I was rebuilding the engine anyway. I think you'd get about 170-180bhp from just that, but duelling would be the main issue with standard ecu. With an frp ecu, you can fuel fine upto about 7psi. Mine was about 170-180, & had lower compression.
I suppose it all depends on budget, skill level,& the amount of power your looking for, I truly believe that the 1.7 is a very very strong engine, I'm running 230bhp @ 12psi, on all standard internals & have been running 7psi for 2k miles now, & it's not missed a beat! I've messed around with lots of things, fuel pressure, cam settings, boost, rev limit (I've tried it at 7400) and it purrs like a kitten!! I think these engines will take 250bhp, but you'd struggle with injectors, I tried mondeo side feed injectors, and it ran like crap! Also getting a strong enough 220mm clutch, my paddle clutch needs uprating, it was ok at 200, but now it slips/judders when trying to accelerate in high gears!