Depending on where I am (and how hot it is!) I use a Jerry O'Connel Basic wallet or a wallet which is gaffed a la Real Man's Wallet. I also have a Mirage wallet but haven't audience-tested it yet.
The O'Connel wallet is a long jacket wallet with an "external" loading method, into a zippered compartment - the other works the same as the RMW.
One tip I have for the RMW-type wallet is to have the flap of the poppered compartment open in your pocket. This will act as a natural guide into the compartment. When you remove the wallet, do it slowly, so that you have time to "pop" the flap closed. Apologies if this appears in the instructions to the actual RMW!
Also, I have found a useful method for ensuring the gaff doesn't stick with the Mirage wallet - when you go to remove the "card", wiggle it around and open up the pocket slightly. This does two things - it loosens the gaff and cements the illusion that the card is held tightly in the pocket. When the actual card appears, the "snap" therefore seems natural.
As for whether to palm or not, I use the Jennings Immediate Bottom Placment, as mentioned above, to control the (signed) card to the bottom. It's easy to cull this away in your right palm as you reach forward, offering the spectator to shuffle the deck with your left hand. Act casually and they won't suspect the palm.
Also, as the palmed card has its back outwards, there's an inherent advantage when you load it into a wallet. When removing the card, the spectator will see the back of the card first, then the (signed) face, heightening the magic.