Posted before but thought contemporary advertisement might fit here:
I keep a Spotmatic on the shelf as I like the ergonomics but that could be because it was my first SLR. My dad gave me his camera and a three Takumar lens set. All have moved on but I have repurchased a Spotmatic in better condition - Dad's was a bit run down internally and was scratching the negative. It is a great camera for continuing to use the M42 lenses that seem to come and go at my place. I have thought of moving it on from time to time but at the return it commands it is just not worth it. I keep batteries in it and give it a few test fires every couple of months.
This is my copy and just for fun I took the pic with a ST 55mm 1.8 at about F2. (using the K3) It is in good cosmetic condition as it has had the full Eveready case on it all its life by the look of it and even the case is in good condition. Probably needs a CLA internally.