Magnepan 3.7 or PSB Synchrony One?

Thank you Djcxxx -
I know and it seems to be the nature of things. Audio is a pursuit of passion and as a result opinions, likes, and dislikes get defended. That's part of the fun. :-)
I agree listening is the optimum way but I'm in the 'sticks' so it's not always and easy thing to accomplish.
I always like to hear from others. In part because it's very easy to get impressed for a short time by something,especially speakers, and later find out what seemed a minor flaw in the beginning is something that wears on you long term.

i've got no dog in the hunt, but have auditioned and was very impressed with both (which, as above noted, really are different animals). the psbs to me were a great all-arounder with no discernible weaknesses--detailed, full range with seamless driver integration, i do not find that they "present a small image"; i think they have a significantly wider soundstage than the 3.7s, which have a more limited sweet spot. the 3.7s are obviously bigger, more challenging to place and drive and definitely need a sub (or two). however, they 3.7s present as transparent, lifelike and natural a sound as you'll hear, even more so than the very transparent psbs. the practical choice here would be the psbs, since they're less dominant aesthetically and you don't have to invest in the high-powered amps, subs, etc.; however, if you willing to make the commitment and wanted the best sound in a dedicated room, the 3.7s might be the choice.

What size is your room? The 3.7's are the far superior speaker overall, but
to get them to true potential you need a very good amplifier that can put out
some stiff current. For example, there's a great deal on a Musical Fidelity
A5 intergrated amp on Audiogon that would be a great match for the
Maggies.

Patrick, you didn't say what kind of music you listen to, or how loud. The story with the 3.7's (and other Maggies) is that they're an easy amp load for a real amplifier (e.g., one that can double down into 4 ohms rather than a cheap receiver), but inefficient. Often, you'll hear talk about limited dynamic range in Maggies when someone just hasn't used an amplifier that will drive them to their potential. They can happily suck up 1000 watts per channel. But here's the thing -- people tend to turn them up at the store, but not at home. So most people don't need an amp that size, something like 250 watts per channel will do for most listeners. But it's impossible to say for sure without knowing how loud you listen.

In general, I'd say go with the 3.7's if you're concerned with stunningly realistic reproduction of acoustical music played at up to plausible levels. If you want to play rock at gut-thumping levels and have more of an instruments-in-your-listening-room effect, dynamics (or larger planars) can be a better choice. The Maggies by way of contrast are magic carpet speakers that if properly set up will transport you into a larger acoustical space.

I'm a line source dipole fan myself -- they have a realism on acoustical music that boxes lack. But this is my personal bias and I agree that you should listen to both, because preferences vary. Unfortunately, Maggies require careful setup and the box-oriented acoustics at most dealers don't suit them, so unless you have a friend with a pair it will be hard to hear them at their best. That's a consideration at home too, you have to be able to pull them out 5' from the front wall if they're to perform at their best, and they need a fairly plain wall behind them to image properly. Forex, I can't use them on the wall that has a fireplace mantle, the image isn't as good. If you can give them that and take some time with positioning, they're less sensitive to room acoustics than boxes.