I recently went from 8' Talons to 15'ers. Top end speed dropped by approx 3 mph and slower hole shot. Not only are they heavier; but are higher by approximately 10".
I decided to make this modifcation and ordered an additional pair of Support Post Assemblies from MinnKota (Approx $60.00). The dual support posts seem to provide a solid brace for the Talons. I moved them toward the top of the Talon and lowered the posts to where the black box is approximately 4" above the deck.
When running any distance, I'll use the ratchet strap to secure them to the deck by attaching it to the boat cleats. Weight is now reduced off the tail and spread out over the rear deck more.
Prefished a small lake this evening and didn't have the distance to see what top end would be, but much improved hole shot. Similar to what it was with the 8'ers.
I'll post what my top end is once I have a chance to open it up.
I'm not sure if this mod will affect my warranty.