That lens was one of the finest examples of it's kind just a few short years ago. People raved about it, took excellent photos with it, and generally loved it.
Then the II came out, it's better, but incrementally so, and the cost is very high. The same goes for everything in this business. The new XXD is out and it's the Shiznet!! My old XXD is junk!! the reality is your XXD or 70-200 was just fine, and raved about on it's introduction, it still is great and will continue to take fine photographs. If you're happy, get out and shoot. I do have a II, but it's not groundbreaking, it's incrementally better than my old Drainpipe, a 30 year old lens.
Rule books are paper they will not cushion a sudden meeting of stone and metal -ekg-