Well…had a listen on my system (in sig) and there is hardly a difference, the mastered version sounds ever so slightly wider but that’s about it for me, frankly whichever version you want is ok for a listen, if you put them up without labeling them I don’t believe anyone would know which is the mastered version, I’ve gone through the same hassle and have come to the conclusion that mastering isn’t worth the hassle (for me personally)
there was never enough difference for it to be worth the work.
clearly there is an awful lot to mastering and if you can’t get an expert to do it I believe the time is better spent doing another song.
cheers, Kevin