you mean cost less, than yes, but better.... well it's a matter of opinion and depends on what you mean by modify and what it is your looking for exactly.
a modified d5 is typically more expensive than a standard rebuilt d5 because of the rework time to change the convertors drive and driven members for increased rpm to be gained before transmitting force to the turbine.also these modified d5s usually include the additional time and labor to weld the pump and turbine fins for increased long term durability and consistant performance over the stock bend over design of fixing the fins.