The exhausts are fairly simple bolt on jobs. The only problem is getting the tail pipes even and not rubbing. Take it to Joolz, he will do it in an hour and charge you less than the cost of scraped knuckles
The only other problem is your ear drums, waking your neighbours and track days. I would suggest considering just the decatting route and not going for a sports exhaust or going for sports exhaust and leaving the cats on. The former is cheaper, sounds great, spits flames etc...
