When Bleem was originally released it became an instant hit and received media attention after its creators were sued by Sony. After a number of updates and a promise of frequent updates, it has received no update since late 1999. The major of Bleem was the ability to get increased performance in games using 3D accelerators. Many games released before the last update likely work, but few released afterwards work.
Until recently Connectix owned sole rights to VGS and had an ongoing suit with Sony. Recently Sony bought the rights to the VGS. The future of VGS is up in the air, after June 30, 2001 Connectix will stop selling the product. The main draw of VGS is strong compatibility with the Sony Playstation. The drawback is no improvement of the graphics with the use of 3D cards. There is a large body of freeware programs that improve compatibility and features of VGS.
The newest of the mainstream, ePSXe has become the emulator of choice. The main detractor of it, is that unless you a Sony Playstation it is illegal to use the emulator. The reason for this, is that the bios file required to run this program, is Sony's an they only sell it in Playstation. Most major games are playable, and many other titles work with only minor errors. The emulator uses a driver system that is used by most Playstation emulators. The emulator allows the most control over what goes on, but has a much higher learning curve.