I can't yet compare the Sledge but the Extreme Flight profile Edge is definitely better that either of the two Goldberg ARFs. I have a Sledge kit waiting it's turn on the table but it's about fourth in line. I can't blame you for being hesitant what with the price of the Sledge. By the time it was done it will have cost more than the Arfs!
Mine will get built though, hopefully this winter.
Matt