I've been using a V1 (3.864) for quite a long time. Maybe this falls under "don't fix it if it's not broken", but I'm itching to try something else.
The 8500 x50 was in my car for a few weeks before the V1, but if memory serves, its performance was just shy of the V1's. I don't know which horn it had, but going by Mem-Tek's explanation of the M4 vs. S7 issue, it probably didn't matter all that much. Then again, it was an early x50 build, and he did suggest that there were horn improvements made to the M4 platform since the early days.
Have never used the 9500ix or Redline. I don't particularly care about GPS functionality, though something a little less chatty than the V1 would be nice. Most of my driving is in the city.
All that said, I'm just curious as to whether it would be a silly thing to try and snag a blue 8500 x50, S7 or M4 (which apparently no longer matters like it once did?), from the Escort eBay store considering that I'm currently on a V1. If not that, is there anything about the 9500ix that makes it worthwhile besides the GPS/lockout functionality? What about the Redline?