There are quite a few options:-
Blueflame - good brand maybe a little more expensive than the two below. I have heard both praise and one complaint about them, but the ones I have seen have been spot on.
Powerflow - I've seen pretty much 20-30 different types of these which range from the sublime to the ridiculous. Choose your dealer wisely if you go with this option. The "chav" tag is undeserved, but it does tend to attract those with a lower budget. You can ask for higher grade stainless piping, but you would probably have to wait for it and it would cost more.
Exhausts UK - specifically targeted for the "max power" crowd. They do reasonable work at a good price and tailor make to specification. I don't know if they are a Franchise or Sheffield specific though.
I know you mainly want the noise and bling Ollie, but you generally get what you pay for in the exhaust side of the modders world.
If I was in the same boat as you I'd probably ask each one what they can do for you, what sound options they have for their back boxes, what tailpipe options they can give, what grade of steel they use, what guarantee they offer, what price they can offer and how soon they fit.