From what I understand, it is no different from other structural epoxies like System Three T-88. T-88 is $22 for a 16oz kit. Bladebond is $28 for an 8 oz kit. Maybe they re-package some good grade structural resin and sell it as a knifemaker specialty product for twice the price.
I can say that System Three T-88 and West System G-flex meet every knifemaker requirement that I ever found.
For hidden tangs, I use System Three mirror coat or clear coat. It is very thin and pours right down the hole. It is not a thinned resin, but a 100% solids type. It cures HARD. The slow cure allows doing multiple knives at one time. You have time to check and adjust the blades and handles, then clean up the excess without rushing to get it done.
A 16oz kit is $40, as opposed to a 6oz kit of bladebond-HT for $17.
One other thing is the fast cure time of Bladebond. This is accomplished by putting in more peroxides as accelerators. This makes for a weaker resin. While it may be more than strong enough, I would highly suggest that all knife bonding be done with 24 hour resin. It helps prevent errors as well as makes the strongest bond.