Get it. It's gorgeous, as are all first-series Series 1 primes. At that price I'd seriously consider buying it as a spare. The 200/3 is even nicer. Both focus incredibly close. I also have the 90/2.5 and 600/8, and used to have the 28/1.9 (a friend REALLY wanted it) and 800/11 (too slow, and too close to the 600/8). Actually the 35-85/2.8 Varifocal is astonishingly good too, though the 90-180/4.5 close-focus shows its age compared with primes and more modern designs (I have both those too...)
I agree with you on all except the 90-180, you must have a bad one. I recently got a 24-48 which seems good. Problem is if I packed all my Series 1s to travel South I would need a porter.