Pick the one you like but sonically not that big of a difference. Turning the loudspeaker 1/4 inch makes a bigger change. The biggest improvement they make is on the smaller panels that get the tweeter level up a little higher. On the big panels (1.7 and up) it’s not needed but like you already know they are more sturdy.
P.S. Get the 3.7s they are a step up from the 1.7s, you will not be disappointed.