If you're looking for somthing servicable and cheap, Walmart sells a semi-circular, rubber-backed, tightly woven rug that is a great practice pad. The draw-back is that it looks more or less like what it is: a cheap rug.
The Maniac pad is a comparative bargain: hard board, nicely padded, cool brass corners, and it looks good. But mine had a fundamental design flaw when I bought it.
The pad has a couple of hold-out slots for cards and coins in the back. When I purchased mine, they had mounted the feet in a rectangular pattern under the audience-side 2/3 of the board/pad. (Instead of in the corners of the pad.) The result was that the pad was prone to popping up if I rested my hands too hard on the back third.
Some would argue that this isn't a flaw, but a feature. (You can do impromptu spiritualism effects: "And now, by the occult power of the great spirit Fulcrum Numismo, watch as all the coins go flying onto the floor!")
Me, I just moved the back two feet into the corners--where they belong--and called it a day.
I think, to some degree, which pad one chooses is a matter of personality. (Or lack thereof.)
I've experimented with a variety of things, including tightly woven Persian rugs, big mouse pads, and a D. A. pad from Mr. Busby. All of them are servicable to one degree or another. The best advice is to find something cheap to practice on, then when you feel like you're ready to perform, choose which ever pad fits your style and presentation best, then practice some more.
But, like Alain said, if you've got one, spend your time practicing instead of shopping for pads. When you know which kind of magic you really want to present, you'll know what kind of pad--if any--you need.