The Pentax SV, S1a, or any of the Spotmatics were just delightful to use. An advertising slogan used by Pentax when these were new was:-
'Just hold a Pentax'
One you had you knew what they were talking about. Anything else was an 'also ran'. They didn't come anywhere near for quality, balance and reliability. They had a microprism focussing aid in the centre of the screen which has never been bettered. Absolutely superb.
One little quirk that came with the S1a and Spotmatic SP500 models was, the shutter speed dial had one extra notch AFTER the 1/500th sec mark. This was actually the unmarked 1/1000 sec position for the other more 'sophistocated' models. In fact it was the same shutter with a 1/1000th second position but the shutter speed was not calibrated for accuracy (but in fact was usually not far off).