Just out of curiosity.
What RPG that had multiple editions did you decide to stick with an earlier edition rather than "upgrade" to the new edition? Why? What about the earlier edition made you decide to stay with it? What about the new edition made you decide not to go with it?
What about you? What game did you stay with an older edition rather than adopt a newer edition, and why?
Many over the years.
D&D - went back to Cyclopedia after 3.5e came out. Also after 5e.
Traveller: I stuck with MegaTraveller (MT) after TNE lead to subsatisfactory play. then again after T4. Then again after T20 and MGT1. MGT 2 hasn't seen table yet... but probably won't.
The One Ring: 1e is far superior, especially in the revised rulebook (1.1) to 2e; hope has a known effect and thus isn't wasted, and the TN calculations are easier, combat feels better, too. Only the 2e travel is an improvement over 1e.
Legend of the 5 rings: at first, I started with 2nd... then to 2nd with 1st rolling, then got 3rd, but went back to 2e due to the wider range of schools, collecting 3e until there were enough 3rd choices... got the core for 4th, didn't like the simplifications, stayed with 3rd... until playtest of 5th. I have since stuck with 5th - current sunday game is moving to L5R 5th again.
Star Wars: Started with WEG 1st, then with the RC, then on to 2nd... and liked it, didn't like 2 R&E as much due to scaling rules. Got, tried d20 SW, bounced hard. Tried revised, bounced harder. Both times, back to WEG 2.0. Switched to FFG during playtest but have run 1st and 2.0 since; 2.0 is just a hair behind FFG for me, but is an open option for players to request.
Twilight 2000; Prefer 2.0 over 1.0 and 2.2; I like the skill only rolling better than the att+skill of 2.2, as I feel 2.2 overvalues attribute:skill balance. I skipped 3rd entirely, and have since switched to 4th.