I've never gone as large as 19" wheels and it's highly unlikely i ever will.

My experience of wheel changes is mainly with Mercedes W124's, i've had the standard fitment 15" and i ended up with 17's mainly because aftermarket 16" wheels are/were very hard to find at the time of purchase, but would have been a better bet IMO.

I suppose my move from 15 to 17 is about the same difference as your 19/17 dilemma....though if there's a 16" that could fit your car i would certainly consider that too.

The 15's certainly caused roll, the 17's cured that completely and provide a taught handling and stable platform, able to corner with complete stability at quite severe loadings which the 15's would have been most uncomfortable with.

Of course there's a downside and the big one is the loss of the magic carpet ride quality, and after all these years i'm not so sure that i wouldn't back to standard except those times when clear roads and the right combination remind one of why the change was made.

The other major downside is that the lower the aspect the less sidewall there is to protect the wheel, and tyres usually (not always) get to be silly prices too the larger and smaller aspect you go, and IMO the larger you go the better the quality must be in order to keep wet grip standards up.

The worse full out rear wheelspin i encountered was at around 50 mph on the 15" with the Firestones the car came on when we bought it 12 years ago, hit kickdown in the wet and the rear end just span up into full spin, no TC or ASR fitted, most unnerving and saw those F'stones removed immediately.

If i could do it all again, i'd have kept the 15's for winter use and just had the 17's for summer.

Gone back the other way now, just bought an old Landcruiser sitting on 16" 75 aspect tyres, thats more like it, not much chance of kerbing those and it's had the desired effect of slowing me up, which was needed.