From what I have seen of these bows, I believe they from the BowTech/Diamond lineage.

Over paid? I don't really know. It really depends on the price of the bow compared to a model comparable in the Diamond line along with the quality, shootability, durability, etc of the Gander Mountain bow vs. the Diamond bow.

Did he shoot both the Gander Mountain bow and a Diamond bow? What did he try out before he decided upon the Gander Mountain bow? Was this the best feeling bow of the bunch?

If he likes how the bow feels, I guess it really doesn’t matter. But then again, if the bow doesn’t have the quality of a Diamond bow but shoots the sameall the while paying more for his Gander Mountainbow, I would say he did exactly what you think: overpaid.