We also took an endowment mortgage in 1991 and were told it was the best thing since sliced bread and that whilst they were under an legal obligation to show us 6%, 9% and 12% returns, that in reality we could expect much higher.
The advisor was wrong.
Luckily we were compensated and were in the same posistion as if we hadn't take it out.
But hey don't listen to us. The guy with the vested interest knows best