Ah, I see! Well, then I'd guess either way is fine. It can't hurt to have a local NHS GP. At least that way you'll know you wont' have to pay for that regardless of what your insurance company says!
But, as I pointed out, some specialists don't require referrals. And just because your GP gives you one, doesn't even mean they know the specialist they nameor how good they are. They may just refer you to the closest one or the one their office always uses, etc. If you have the luxury of private insurance, you can probably do some research into who to see. Obviously, this is a great benefit if you need serious medical care.