I like a good ribeye steak, they can be tastier than yer fillets and sirlions, and a bit cheaper. Get one with nice bit of fat in the middle.
If I'm feeling flush I'll go to the posh butchers and get a Barnsley chop... super tasty with crispy rind, but expensive. I go to Scotland regularly, they have far better and cheaper butchers, and I bring back a few Gigot chops, essentially the same as a Barnsley chop.