does a 'not for road use' race can make it dificuilt to pull away smoothly? are they suited to flat out racing only?

It's not the can but the Engine mapping/carb jetting, the only way to set up race cans is on a Dyno.

Adam.

exhaust is fine mate, just means its loud

"not for road use" means an MOT fail next time, unless you put on a road legal one for the test.

The "Race Can" should not cause problems pulling away.

however you really should re-jet your carbs or re-map your injection.

Fitting a "stage 1" or "stage 2" set of jets for your carbs might help, but the best option is to have a professional put it on a rolling road/dyno and pick the specific jets (or re-map the cpu for the injectors) depending on where you want the power distributed. (If your paying to have this done, then it's worth getting a K&N air-filter fitted first)

A lot of accessories are marked "NOT FOR ROAD USE" when it doesn't really matter, However with Exhaust systems IT DOES. The main issue you will have is at MOT time due to them being loud, and it all depends on the person doing the test - some places will straight out fail you bike for it, Some will charge a fee for 'lending you a road legal can for the test', some might just want proof that you have a road legal can - even if it's not fitted, and in a rare few cases the MOT tester will temporarily go deaf during the test ;-)

thanks for all the help guys, how much does it cost to get it dyno tested?

http://www.dynojet.co.uk/tuningcentres.php?type=3

As with anything the price depends on where you go... Follow the link to find somewhere near you and ask them.