910 is economy 5904
Suggest you compare from there; 910 has plastic rear sight, 915 is metal blade; 915 seems to me a little closer to XM-10 submission to military contest that gave the US army the Beretta 92. This is the historical trail; THE SW SUBMISSION WAS NOT INFERIOR IN ANY WAY TO THE BERETTA and possibly better; I like the way it handles better.
At any rate, price seems a bit high compared to 5904, 5906 (SS) or 5903 (alloy frame). I own 5903 and swear by gen 3 smiths; but think the price you mention is high compared to market for a 5904; rather hunt for a 5906.
Economy series however are reliable performers even at value prices. Suggest comparisons with Gunbroker listings at least as a price guide.
I'm shopping for a 915 top end for my 5903 at the moment FWIW. Also own 3914(single stack) and have owned 6904 I wish I'd kept. Traded for 4516 when they were new. Love the gen 3's. 457's are sleeper/keepers of value series in spite of plastic sights.
Cheers, TF