Well, I have an M260 as well, but I've never used it. Why? Because I have other mics I like better. The M260 seems to me like a very neutral mic, with not much proximity effect (and no, it's not the 260.80, it's one of the old ones). Like it's suitable for radio announcers. Maybe that's good, but it doesn't float my boat.
I've had pretty good luck buying old Shure ribbons on eBay. I have a 333, a 330, and an SM33. They're all pretty much the same mic (different finishes, and the SM33 has impedance selection by wiring rather than an external switch). I sent one SM33 back to the seller because it had some fuzz in the sound, but the three I kept are great; and none of them was more than $400. Also got a 300, which is a figure-of-eight, and it's good. These are all long-ribbon mics (like 2 inches), which have that low-resonance thing Harvey Gerst mentions going for them. The Beyer mics do not. I figure that, now that I have all I want, I can share the secret.
As far as Beyer, I much prefer the M160 to the M260.
I do have some AEAs, and I use those as much as I can. But the Shures and the M160 really get used quite a bit too.