If you're mainly leaving one lens on, I'll also recommend a Pentax Spotmatic.
The remaining disadvantages: slightly murky viewfinder (not a big problems with a fairly wide wide), slow metering and averaging meter (as opposed to spot or center-weighted) may or may not be important to you.
On the good side, they're cheap, very reliable and have good ergonomics.
A number of good lenses are available for it, including the Zeiss Jena 25mm. Also look for Mamiya M42 lenses.
IMHO the Yashica FX3 isn't especially durable and the leatherette falls apart very quickly.