Re: most likly buying a prs....mccarty or custom 22?
Having more PRS run through my hands than I care to think about I'll try to give you my somewhat-but-not-really qualified advice.
The only two PRS that have stayed in my hands are a Cu22 and a singlecut. However, I would actually probably prefer a McCarty to my Cu22, but I won't be selling my Cu22 as it is an artist package and is cosmetically dinged enough that I'd be taking a huge loss on it if I sold it. It was also bought (at least half of it) for me as a present and has been the guitar I cut my teeth on in the music scene and also sounds **** good.
I like that McCarty's are a little thicker and used to own a MC Standard, but sold it as I was never able to get it to sound quite right. Might have been that I was used to having a maple cap on my guitars, might have been the pickups I tried in it (probably the case) or might have just been a bum piece of wood (happens to every company once in a while). The McCarty just feels 'right' in my hands. The thicker body feels a little better to me than a Cu22. But that is not to say that a Cu22 is bad. Hell, I've got a great one and had another really good one that I sold because I realized I don't like tremelos.
Also take note that I stuck with a singlecut. I know it isn't what you mentioned, but they're the best guitar PRS makes, IMO. Try one out. You might be surprised. I especially would like a SC245. But my Singlecut that I currently own (and the one I sold to my dad) are my two favorite PRS guitars. Take that for what its worth.
As for what you mentioned, I'd go for the McCarty in tortoise shell. But then again, I like the Wide/Fat profile (only option on the MC) and if you like thinner necks you might want to go with a Cu22 (unless they now offer the wide/thin on McCarty's).
As for 10 tops, birds, etc? How ornate do you like your guitars. Both my PRS are opposite ends of the spectrum. My singlecut is solid paint (no 10 top) with dots and it is every bit as good as my Cu (artist grade top, paua birds, gold hardware). I'd personally not opt for birds as they're expensive and no one can see you have them unless they're up way close.
10 top? I've got mixed feelings. Some non-10 tops look every bit as good as a 10 top, kinda just luck of the draw. I prefer plain paint, however, if I'm going to have a stain, I prefer a nice grain to the maple. Basically if you are ordering the guitar and want a nicer top, ask yourself if the extra money is worth it. If it is, ordering that option helps to guarantee a nicer top. It is luck of the draw otherwise. If you're not going to buy new, just inspect the guitar. You'll find that some non-10 tops look stunning. To me it comes down to whether you're going to order this guitar or buy one that is in stock, if that makes any sense.