Both the All Star System Seven Series: FGS7-FB First Base Mitt and the Mizuno Pro Soft will feature high quality leather. As to which one will last longer, that is hard to say as there are so many factors involved to determine the overall life of a glove. Please refer to our glove resource guide below for tips on how to properly take care of your glove and prolong the life of it.
Typically, for a 14 year old fastpitch softball player, I would recommend a female fastpitch glove that features a 12.50 inch pattern. The All Star System Seven Series: FGS7-FB First Base Mitt features a 13.00 inch pattern and is geared towards a male's hand so it may be a tad too large for your player depending upon her hand size.
We should be getting the right handed thrower option of the All Star System Seven Series (FGS7-FB) back in stock within the next two weeks or so.