sustanon and propionate

Im taking 500 mg of sustanon a week, and a buddy of mine gave me a 10cc bottle of testosterone propinate 100mg/ml. Im thinking of shooting in 250mg(1.5 cc, and 1 cc 3 days apart) of prop a week to speed up my gains. I know sustanon already has prop in it. I dont want to waste the bottle, and might as well use it up for a month. What do ya bros think about that? Is this gonna screw up the sustanon's time release formula, or its effectiveness? Thanks

I would just hit 100mgs/EOD for 3 weeks.By then the slower acting esters will have started releasing and saturating your system.