do you have a link to the Protos ones?
I am just ware there are a lot of alternative designs about which do not really hit the mark.
The Morrant one, it is hard to describe are almost perfectly ergonomically designed. All the folds and sahoping is in the right place and they feel almost perfect, but because they are injection moudled and are left maluble than normal pads, if this design was not spot on then i think that they would be no where near as effective oras comfortable.
The best thing about the mrrants, other than being feather light and protective is that you dont feel like you are wearing any pads. I strongly doubt cheaper alternatives would. THey would feel like wearing funny looking pads, and certainly not Morrants.
In short, Morrants are different gravy and well worth the investment.
Other makes, for me woudl just feel exactly what they are cheap alternatives.