I tend to avoid putting slide film in certain cameras. Mostly my SV, Spotmatic, KM and K1000 as the light metering on these just isn't accurate enough (they probably need a CLA but given it's only the meter that's out I'm not too bothered). I also try to rotate them as I know that long-term storage does cameras no favours - they need to be used. At present I have:

KX loaded with 200ASA slide
ME loaded with 200ASA colour negative (rescued roll, it was in an ME F which died with a shutter fault so I hope I've only lost the four frames or so).
P30n with 200ASA colour negative
SF7 with Ilford Delta 3200

Next up will probably be the K2 with Delta 3200 and a couple of MXs with B&W and colour negative respectively. I only have one more roll of slide film left and the local shop has stopped selling it, given the extra hassle involved in non-process paid slide film this will probably be my final roll, so it'll go in something a bit special.