I own and still ride a Proflex bike. Mine has been cared for over the years as I'm the original owner so I know it's in great shape. Many of these I've seen for sale are destroyed and probably unsafe. If this is an 857 or 757 that looks in good shape it could be worth checking out otherwise go elsewhere.

Have you stopped off at your LBS? I got my son a GT Palomar for Christmas and for $330 that bike is really nice.