Both Onhwy61 & Sbank's post's are exactly right. At least I think so.
"Both brands have equally terrible resale value, (just saw a pair of 3.7 go for 3k on Audiogon) So, not concerned with that aspect. So perhaps, Ill grab a pair of 3.7 used and convert to "i" status and play both in my system and see which one gets put up for sale.
That was my plan at the outset, before I get started, I was just was curious if anyone else has compared them properly as both speakers receive the most accolades from reviewers and fans alike for the 5k and under category."
That's a good idea, but with those 2 speakers, its easier said than done. I was never able to get a good demo of Magnepan speakers, so I went out and bought a pair of 1.7's. I put them in the same room as my Vandersteen 2's and did the type of comparison you're talking about. In the end, I feel it was worth the effort, but I can tell you that you'll need a variety of equipment for best results. The setup needed to get the best sound out of both pairs of speakers was very different.
Your current components may be a great match for the 3.7's, but I wouldn't count on it. My recommendation would be to see if some friends, or even a local dealer, will lend you some alternate gear to try. Someone above mentioned Rogue. Cable Company is a Rogue dealer. You could have them send you some components to demo.