I pay about £12 a month for my pet insurance, I took it on when I took a springer off one of the missus's friends that was'nt looking after it right, the springer died of cancer a few years later then I bought a giant mutated labradoodle, every bill i get is around £50-100 quid, when the springer had to be put down, the new giant had bad ears and blood in his poo each costing me a £50 visit to the vet, my pet insurance only pays out after £80 and I have to pay the first £80, so basically it has paid nothing to the health of my dogs but if I cancelled it my dog would no doubt break his leg and it would cost me a fortune.
Your buggered if you do and buggered if you dont, be very selective and read carefully what it is you want, most standard vet bills will be around the £50 mark which wont be covered due to the excess, in my opinion a springer is a working dog and you wont take that out of him, they run and jump everywhere and eat everything in sight (they will even eat slugs and snails which can kill them) so I would have pet insurance to cover the obvious broken leg bills which can be in the region of £500 but make sure that the excess on the policy isnt so high that the smaller things your dog needs doing isnt going to leave you out of pocket.
hope you have fun with your springer they certainly are the most loving dog you could ever own but must be walked plenty or they become very frustrated, also they are massive company dogs, they dont like to be left alone for long periods and that was the only reason I didnt get another due to the missus working now.