This really depends what you are looking for.
-Pro-body, solid build, good viewfinder with all relevant information, relying on batteries, aperture-priority and manual metering: RTS II
-Very compact, almost all important features except mirror lock-up and shutter speeds over 1/1000, manual wind, aperture-priority and manual metering, batteries needed: 139 Quartz (159mm is as well nice, but they are hard to find and on Contax bodies I've used it is the only one that has failed, couple of times actually...). If you can live with viewfinder showing shutter speed only, aperture not visible and double exposure is not a big thing, Yashica FX-D is very very similar than 139q. You will as well miss TTL with flash with Yashica, but FX-Ds are typically dirt cheap. Control lay-out is different between Yashica and Contax.
-All manual, FX-3/Super/Super 2000. No info on viewfinder, except 3 light lightmeter, light and compact. FX-3 Super is the camera I take when it is raining

These are pretty cheap as well.
-In-built winder,matrix metering, spot metering, center-weighted metering, all exposure modes and all the info you need in viewfinder. Compact and light: Aria.
139q and FXs will need their leathers most probably to be replaced. Aria and 159mm do not suffer from that. RTSII seems to as well have better quality leather. On the cameras mentioned above RTSII and 139q get the most usage. They do everything I need and nothing gets in the way while shooting as I am on aperture priority 90% of the time. While buying check that mirror has not slipped. Google for "Contax mirror slip" and you get what it is all about. Best bang for the buck I'd recommend the 139Quartz, unless a bargain RTSII shows up.