comparing raw dyno numbers is pretty useless
factors
humidity
altitude
temperature
wheel size & weight
tire size & weight
engine condition (old, just tuned up, rebuilt)
what intake?
what exhaust?
what where the dyno plots instead of peak #s? (if you gained 5 hp across the board and significant torque in the low to mid rpms then that is pretty powerful even though a max of 5 hp doesn't sound like much)
...there are many more variables and not just these

on its face i wouldn't say that was a waste of money as we don't know the complete picture