Mine has quite a few games on, nearing 100 by now. It shines up very fast but I have not noticed any reaction loss, it just seems to be appearance to me. I do clean it always and will refresh the cover from time to time but haven't done any more than cleaning in probably 40 games, it isn't tracking up for me but it is shining up.
My buddies are all in the same boat as me, it just shines up, one just got a Virtual and it isn't much if any stronger than the dimension with similar layouts when used on the same conditions (the hook is just about identical but the Virtual is a little longer and stronger).
And to end the blabbing, I wouldn't worry about it.
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