It depends. Most of the RWD cars are getting older and suffering more issues simply due to age. The last of the RWD cars was the 960 (ended in 97)/S90 (out with 1999), which were pretty much more or less bulletproof. The FWD started with the 850 series, and lived on to all current models. The earlier 850's and S/V70's contained far less fancy electronics than the newer models. I own an S70 myself, and it has had its share of electrical issues, but most can be solved without a computer software upgrade (dealer = $$$) like many of the newer models require.

If you are looking for a P1 FWD car, stay with a 98 or earlier. P2, 2003 and later. Avoid the models in between.

Any year 960 93 or newer or -90 would be just fine by me. The S90 was essentially given new bodywork, and nothing was changed.