Professionally speaking Tubedude is right. What is the site
www.thelisteningsessions.com I hope that's the right URL. If not, it's on another thread, do a search. Anyway, you can hear the 'same' recordings of different instruments going through a Great River, an API, a Neve, etc. Differences are subtle to most ears but as you listen a few times you will hear them.
I add this though. Some of the better non-eletist pres will probably do great in home situations. If you are running a commercial studio or plan to, save your money and get one of the top dogs..the single Great River unit, Neve portico, I was recently looking at
Universal Audio 6176 but decided against it in the end.
The Jomeek 3Q, for example, I have heard is a really well-made unit. Alot of people seem to like the DMP3 as well. When I first started building my setup I bought a Joemeek MQ3, the 3Q's predecessor, and I still have it. It sounds great for what I use it for, and it definitely gives a 'big' sound compared to standard board preamps. The new Joemeeks are reputed to be less colored in sound, therefore more versatile if this is to be your main channel for awhile. Grace 101 gets good reviews as well here. Probably more respected by the pros, in general, if FMR Audio RNP. Don't know much about those. My vote would be for the Meek because I have and still use them and am very happy with the products for my application, home recording my own music. If you go to PMI Audio site, click around and you will find 'B stock' as an option from one of the top pull-downs. I think they have a demo or two of the 3Q going for $150 or something like that.