People have had great experiences and terrible experiences using the US healthcare system, and great experiences and terrible experiences using the NHS. I'd venture to guess that, in both cases, the great experiences outweigh the terrible ones.
So. All we can say to you, GGTL, is that you'll have to wait and see. The thing is, as Sara Smile said, the NHS is the system that operates in the country you've chosen to move to. It's the system you're going to have to work with. There's no escaping that. You'll probably learn to love it, as most of us have. But you can't really expect an American-style system when you're moving out of America.
And who knows - you may discover that you prefer the NHS to old American system. And you may even find medications available here that work better for you than what you were using before. And you may wind up with a brilliant GP.
But already finding problems with a system you haven't even tried yet? That's not going to help you at all.
I just want to preface this next bit by saying it's NOT directed at GGTL. But this whole thread just has me thinking about different sorts of expats and the way they choose to adapt to their new home.
First there are the 'adapters' who fit in well and don't find much to complain about. Sure they get homesick from time to time, but that's just natural. And they look forward to their holidays back in the US.
Then there are the 'non-adapters' who don't fit in at all from the start. They're the ones we hear from a lot on this forum because they have the most to say. And in my experience (I've been on UKY for 7 years now and have seen a lot of people come and go), most of them suffer from constantly comparing the UK with the US. And most of them try to live their lives with one foot on either side of the Atlantic.
Again, I just wanted to stress that I don't think this is you at all, GGTL. In fact, from the chatting we've done here and on FB, I know there's a lot about the UK that you love. I think you'll do just fine. But remember - you're not in Georgia anymore! (or you won't be, at any rate)