Just my opinion. Gimmick.
If the bulb is the same size as the Giotto & nozzle same then it would perform equally well on the jet of air emitted..
The air re-drawn thru the cartridge into the bulb is filtered whereas the Giotto it isn't.
But who uses their rocket blower a dusty area with one hand and an open camera body in the other?
Also when you eject air out of the nozzle some air around the nozzle is entrained into the flow anyway.
It's most important to be in a fairly clean area when using it rather than just filter the air into bulb.
If it is a real HEPA then it'll be able to trap smoke, stop bacteria and even fart smells..

I think its bulky and unnecessary.