One of the best cars and cheapest I ever owned was an old omega mv6 expolice estate. 3 ltr (or maybe 3.2, can't recall), lpg conversion, lowered, uprated cams (all done by police). I bought it off my mechanic for a few hundred quid as I needed a car quickly whilst mine was being worked on. I took that omega all round wales as a contractor, driving it through north wales is one of my fondest memories, good power, amazing ride and comfort. Only had it a few months, sold then shortly after the head gasket went - water pipe had come loose and they cooked it.
I also like the passats though, supposed to be good cheap cars.