When we started out in the early 80s in Germany, the predominant cards were Fox Lake or Aviator Bridge size. As a kid, the hands were smaller, and the Bridge sized cards were easy to work with. Almost all the magic dealers had their trick decks, packet tricks, etc. in Bridge size. As in the UK, where they used Waddington’s. You simply grew up with it.
Then, American performers lectured here on these shores, and, of course, most of them used poker sized cards. For us, this was a cultural shock. We knew there were poker sized cards, but only from the images in the (American) literature.
Buying Poker sized decks in Germany wasn’t so easy. You either had to order them in the US, know somebody who had connections to a US military base. Or, if you were lucky, some dealer had a few decks for horrendous prices.
In Europe, you’ll find Bridge sized cards easily. Piatnik’s most successful range of cards is Bridge size. People here are used to Bridge cards, although this has recently changed a bit with the popularity of Poker games on- und offline.
Roberto Giobbi said something along the lines that the aesthetic aspect (Poker size looks more balanced rather than Bridge size) plays a big role. A worthwhile point to consider, but a matter of taste in the end.
From the technical side, poker size is harder to work on some moves. Often, I have seen performers struggling with the Poker size deck and asked myself: “Why doesn’t he simply use Bridge sized cards?”
I have seen genuine miracles with a Bridge deck, and crap with a poker deck (and vice versa).
But the most important point: in case of doubt, and when you see that working with Bridge size is easier and better for you, don’t change the move, but change the cards–use Bridge size.
There is a long list of performers using Bridge size: Alex Elmsley, Nick Trost, Tommy Wonder (who worked with Piatnik Bridge size a lot), Ken Brooke, Rovi, Chan Canasta, Paul Daniels. The list goes on. All used Bridge sized cards to wonderful effect and the audiences ever complained.
When I do stand-up card magic, I often use Bridge, because my stand-up card routines are palming heavy, and it works a tad smoother (I have normal sized hands). For the table work, which involves lots of shuffling/cutting work, I use poker size most often. Depends on the trick.
One enormous advantage of the Bridged sized cards: it is far easier to find wine glasses they fit in perfectly. Try it to find a glass that accommodates poker sized cards, and you will soon find out what I mean.