I understand about the diamond thing too...Since we were in college, I told my husband we could just do bands, I didn't care! My parents, aunts, uncles, cousins did just bands (I think it has something to do with our old Spanish customs, not sure) but he wouldn't have it. LOL!
Anyway, I've looked at that website you mentioned before and always liked it...But I know what you mean...It's scary to order online. Do they have a return policy? If so, just get the setting and see if it's acceptable to you. If it's not, return it
By the way, congratulations on your engagement!!! When's the big day?