The stock blower is about the same as the gen 1 TVS. The Gen 2 is better, but is it worth the cost over a 13-14 blower? I'm not quite sure. Especially since I don't plan on making stupid power with it.
VMP sells the high flow elbow for the oem Ford 13/14 TVS blowers. (that high flow elbow is not made by VMP, but another company). with the elbow swap, you are so close to a gen-2 TVS, that it's not worth the expense of installing a gen -2 tvs.
Story I got was the 13/14 GT-500 TVS is better than the gen-1 vmp unit. So the 13/14 blower is damned good to begin with.