No catch.
Just be sure to check what tariffs they charge once you go over your monthly limit.
(If they offer 500mins and 500 texts free for £30 per month, example what do they charge after that)
If you explain to Vodafone you've been with them 4yrs and have been offered a fantastic deal by such and such a firm and your tempted to go with it, see what they can offer to better it. You may well be pleasantly surprised what they offer.
Also, look in newspapers or internet for offers.
Finally! A subject I can offer advice on!
