"Most of the MAT files nowadays won't work in P4 anyway" 

Haven't found one that doesn't - P4 simply ignores what it doesn't understand. Also, AFAIK, good luck getting Daz Studio to take an unaltered .mc6/.mt5 file. MAT files may be old but they are the universal format thal all the applications understand. If it's for yourself or you want to limit your target audience, the newer ones are fine.

"Democracy is a pathetic belief in the collective wisdom of individual ignorance." - H. L. Mencken