For $20 more than the BD-P1500 will cost you, you could upgrade to the HP21U. This player has all the exact same features that the P1500 has, but it also includes the ability to wire your surround sound directly to the player, by-passing a costly high-definition receiver.
This is a bit odd, because if you have a home theater setup you’re looking to upgrade, this will be worth absolutely nothing. However, if you haven’t jumped into the home theater game, then this would be a great way to already get everything in one package.
The Sharp is a little less, if you’ll pardon the pun, “sharp" than the Samsung. Both players look nice, but the BD-P1500 has the next-gen look to it, whereas the Memorex and Sharp models still look like DVD players that are trying too hard.
If you’re strapped for cash, the P1500 is clearly the best option out of these three, but don’t take my word for it – get out there and continue researching the players. There are more budget players out there that may be more suitable to your needs than either of these three.