I'm selling off all my preamps except my Great River NV & my stock Presonus Digimax pres.

Seriously contemplating an Art Prochannel and maybe an EV 12AY7.

Those who have them, what do you think of them & what do they get used on most?

I owned and used a 2AY7 very briefly but sold it. Not because it didn't sound good, just didn't need it at the time. I only tried it on acoustic guitars and it sounded very good. Didn't like that it didn't have an on-off switch and just seemed to be constructed rather cheaply.

I use my Prochannel frequently, I removed the EH Tubes and replaced them with Telefunken and Mullards. It's a great inexpensive channel strip.

Yeah, the more I read into the 12ay7's, I think I'll pass on those for now.

Dutchman-what do you use it on most?

I use it for Bass and Vocals, It's got plenty of gain (83db I think total)to run a ribbon on a guitar cabinet. I have not been able to use it with the Fatheads on a cab yet. It does get noisy when its cranked. But there lots of gain before the noise kicks in.
The Compressor works great with vocal or Bass, the EQ can introduce some noise but it filters OK, nothing spectacular but does it's job.

The Pro VLAs are $199.00 now if your budget is really tight.(and just need a comp for your other pre's)
http://www.zzounds.com/item--ART212

I have a couple of Pro Channels and the 12AY7. I've put Mullard tubes in all of them.

As far as sound quality I rate them roughly equal. The Pro Channel has a little more oomph in the bass but the highs are pretty similar. They both have excellent depth and a 3 dimensional quality that is my most important criteria for a preamp.

The difference is in gain and features. The Pro Channel has tons more gain and it is set up so that you can really play with the gain staging to go from crystal clear to having some tube growl. It's very well thought out and a pleasure to use. It's one of those pieces of gear that adds an element of fun to recording.

I use my Pro Channel on pretty much everything, from drums to vocals. I have a modded Presonus MP20 that I use on overheads but that's about the only thing I don't use the Pro Channel for. It's pretty clean if you want it to be so it's quite versatile.