I'd be curious to know the weight difference as well but unless all the wings were measured on the same scale, it would be almost impossible to get a real result. These small digital scales can be inaccurate. The digital fish scales are even worse (I have one).

One thing I did notice between doing my Edge wings with epoxy and the Yak with poly, is that the poly is, in my opinion, stronger. I always try to rip the sheeting off of the scrap pieces that were cut off for the leading/trailing edges and the poly glue always took more effort as well as left a lot more foam stuck to the balsa. That being said, how much strength is really needed? If the foam fails before the glue joint, in theory the glue joint was stronger than needed to be.

............Mark