I always forget about my OM kit... I seem to have about 4 bodies, mostly OM-2n, but there's an OM-4 among them. The lenses are very good except the 35-70 zoom which is too soft for a spoiled person like me. However, my primes are wonderful: the 50/3.5 macro, 50/1.8, 50/1.4, 135/2.8, and the oh so lovely 90/2 macro.
I don't use these cameras because they seem too small in my hands -- ergonomics. But all is not lost, I do use the macro lenses on my M240 with great results.
If you find them ergonomic, the OM system is a fantastic value (although some of the lenses command a price). I've thought about finding a grip of some kind to make them more ergonomic, but I have so many other cameras