That's pretty cool. I have two Fireball EL 2.5's, an EX 6.4, an original 1280AT, 1080AT and a 1280S (SCSI) from a Mac, two SE 4.3's, an SE 2.1, a Sirocco 2.5, a TM 2.5, a Pioneer SG 2.1, a Plus AS 10.2, and a few various ProDrives (LPS 540, 270, 170 and ELS 128).
The Sirocco has too many bad sectors rendering it unusable, one of my SE 4.3's recently died (it won't do the seek initialization properly and just spin back down, no idea...) but the rest work perfectly. That TM in particular came out of my dad's old PC after around eight years of constant use; no bad sectors or any problems.
I regret throwing out my two first-gen Barracuda ST32550W's; although I have the disk stack for one of them somewhere. They were the loudest drives I've ever heard! I also had one of those horrid WDC WD93044A 40MB stepper drives, though I managed to do an HD Tune test on it. The firmware was corrupted and it wouldn't show the model number properly anymore, but it still worked!
I've also got the same Conner CFS425A drive as you; working perfectly with zero bad sectors and just as loud I have a Miniscribe 20MB 8425 MFM too, although I have no way to test it because I haven't got an MFM controller card for it, but it spins up without any noticeable problems... anyone want to hear it?