I guess my hands are medium-sized, going a little on small. But that isn't an excuse.
People ask, "Why not use bridge-sized cards? Why use poker cards, that make your life harder?" That is a fairly good question, but I think the answer for me is because I can. That's my point really. The reason why I take up flourishing is not simply to entertain myself and others; it's also to challenge myself.
It's hardly "challenging" myself if I use bridge-sized cards, when I can work with something that will ready me faster for performing the flourish. If you use bridge-sized cards, you're just handicapping yourself and growing reliant on it. Sure, you might say you'll grow out of it, after growing proficient at performing the flourish with bridge-sized cards. And I'm not going to dispute that, because it is true.
But for me, I'd like to remain consistent, and be able to perform all my flourishes with poker cards. Either I can do it with both poker-sized and bridge-sized cards, or I can't at all.
It really isn't a thing to debate about though. It's all about personal preference. No layman is going to point at you and say, "Har har har, you're doing it only with bridge cards, you suck!" I just think you'll be at somewhat of a loss if you're asked to show "that neat flourish my friend said you did last time" when you only have a deck of poker cards on you.
In conclusion, to each his own. Ultimately, I think we're all striving to be able to flourish with poker-sized cards, right?

Let's not allow such a trivial thing to divide our community. Flexibility really is the key, not hand size, and with time, that comes to everyone.