Depends what you pay for your carb'd animal - I'd rather save the frustration by waving wads of cash in front of an ie owner and getting it for say, high £2k's and race it in standard trim than pay £1500 for one and straight away spend £500 - £800 (incl labour) to bring it up to spec.
At the end of the day the ie will be worth more - less damage to my drink everything in the pub fund.