Fiance visa - whats the point?

My UK boyfriend and I have decided its time for me to move to England so we can be together.. so I am in the beggining stages of researching the best way to do this. I have read a great deal about the fiance and spouse visas and I am a little confused about why one would bother with a fiance visa at all? I am an American citizen, so I can stay in the UK for 6 months on a visitors visa and have all the same "rights" as if I went through the hassle of a fiance visa (both would allow me to stay for 6 months, but would not allow me to work). Is the only difference that if we were married while I was on a vistors visa, then I would not be allowed to apply for a spousal visa while in the UK after we were married? Would I have to return to the US to apply for this visa?

It seems like the easiest option would be to marry either here in the US or there in the UK while one of us was on a visit and skip the entire fiance thing all together, right?

Can someone tell me if I am missing something here?

Thanks in advance!

In order to marry while you are on a visit visa (which Immigration Officers frown upon and can refuse entry if they believe this is the intention), you would need to apply for a COA in order to marry. You would then have to return to the US and apply for a spouse visa. A fiance visa would enable you to marry in the UK within 6 months (without a COA), and then apply for FLR(M), and you would then be issued with a 2 year spouse visa.

So then, actually, the easiest thing to do is to get married in the US while he is here on a visitors visa (since we dont require a COA or equivelant) and then apply for my UK spouse visa while I am still in the US and he has returned to the UK... Seems like this would cut down on application fees and time since with this senario only one visa is required. Am I on the right track here?

Absolutely.