The best route would be for you to audition as many of them as you can. Bring reference CD's, and listen to them in the same environment -- if that's a showroom floor, then do your best with it and make do. Make sure volume levels are relatively the same.
Here's my suggestion for a reference CD:
* Burn a copy of 2-5 songs you are familiar with. They could be your own or that of a popular artist -- preferably some of both. Make sure to include some that are bass heavy (dance, hiphop, industrial), and some that aren't. Include some heavy, and some light, etc.
* Take one sample of a voice or instrument -- could be anything; guitar, piano, etc.
. . . and make several versions of it. Make one version dry with no effects or EQ. Then make another version with a 3 db low-shelf cut starting at 100 hz. Then make another version with a 6 db low-shelf cut at 100 hz. Then make another sample with a 6 db low-shelf cut at 40 hz . . . then a 6 boost at 50 hz.
Make a few more samples with reverb added; one of them 20% wet, another 30% wet, and another 10% wet.
The parameters I'm giving you are just suggestions. You can make up your own. But obviously, the idea is to listen to the various options and choose your monitors based on which ones allow you to hear the greatest differences between your samples. One or two of your monitor options should stand out to you very obviously. Like on monitor X you can clearly hear the difference between 20% reverb and 30% reverb . . . or you can definitely hear a difference between a 3 db bass cut and a 6 db bass cut.
And as a rule of thumb regarding reverb, the better monitors will allow you to hear the reverb the most -- very generally speaking.
Anyway, regardless of whether or not you like how they sound . . . the ones that allow you to hear the greatest amount of difference between your samples will probably be the easiest ones for you to learn and for your ears to adjust to. That's going to be the key. Try and divorce yourself from the idea of "which ones you like the sound of," and focus on which ones allow you to hear what's really going on in your audio samples.
I think someone should make this sticky, by the way, because it's some of the best advice I've ever given.
In most of my other posts I'm either stirring up shit or heckling newbies.
