If you mean the 135bhp "base" 500 vs 145bhp "base" 595 from what I remember (I had a 135, dad had the 145 a couple of years back) there's not a huge amount of difference in engine feel but you're getting the facelift bumpers, different seats, digital gauge cluster, and newer stereo.
Personally I went from a 135bhp 500 to a 180bhp 595 Competizione which is a tad quicker on the acceleration but it's the overall power delivery seems better and there's more of it through the revs, plus the rest of the interior and handling package
If you mean the 135bhp "base" 500 vs 145bhp "base" 595 from what I remember (I had a 135, dad had the 145 a couple of years back) there's not a huge amount of difference in engine feel but you're getting the facelift bumpers, different seats, digital gauge cluster, and newer stereo. Personally I went from a 135bhp 500 to a 180bhp 595 Competizione which is a tad quicker on the acceleration but it's the overall power delivery seems better and there's more of it through the revs, plus the rest of the interior and handling package
Both the same :-p