I've always liked Magic acts, though I dislike a lot of the showiness that surrounds them. I appreciate things more knowing the mechanism. For many people the magic is lost when they know the mechanism, I tend to appreciate the ingenuity and skill, I suppose it's part of being a physicist.
Due to my technical interest, I like acts like Penn and Teller - they often show exactly how a trick works, but still fool you with the next step. I also like their sensibility. Their double-bullet catch is phenomenal. People like David Copperfield tend to annoy me due to the over-the-top flaboyance (although the technical side is good). I'm not too keen on the current generation of UK magic types, it's too 'matey'. David Blaine's street magic was good (but the stunts are just tedium itself). For showmanship I loved 'The Amazing Jonathan' when I saw him on TV (missed his show when I went to Vegas).
That doesn't mean that showmanship doesn't count for me, it does, but it's a narrow band of showmanship - I don't want them to try and fool me that it's not a technical trick, that they're doing it with their mind and all that mallarkey - and I certainly don't want an extra five minutes of waffle before the trick is over and they're killing time before showing me the card. I want a magician that essentially respects the audience's intelligence.
David Copperfield, as I said, is an act that has annoyed me each time I've seen it (on TV anyway) for the handwavey stuff. His actual tricks are impressive, but the surrounding showmanship doesn't do it for me. This is a nice spoof of his style, it's really well produced, a simple premise, but inspired.
I particularly like the opening gag, and the bowling alley gag
For a real 'magical' performance, have a look at Robert Strong
Finally, the wonderful Tom Noddy. I first saw him on Paul Daniels' show as a child, and it stuck in my head. Him, the cigarette eating chap, and the bald bulletcatching guy.