The velvets are £40 a pair so the big bore ones will be more exspensive by £10 ish i reckon. It's not just the shocks though it's getting new springs too the standard ones are around £6 apair i think if the big bore ones are the same price you will probably need 2-3 pair for the front and 2-3 pair for the rear so you could be looking at another 35 to 40 quid on springs
All that said they do look verrrry nice also look better anodized red
Paul