Is the MP Compact 2.0 4in recoil spring 15lbs from the factory or 17 lbs?Seller good?

I FINALLY found a place that actually sells recoil springs for the MP Compact 2.0 4in. BUT, their site says the factory spring is 17lbs and that the 15lb spring is for light hand loads only. I had always thought my factory spring was 15lbs... so I'm not sure which one to get. I want the poundage that my pistol came with from the factory that has given me 0 malfunctions in thousands of rounds.

Here's the page. Anyone know the reputation of this seller? : https://gallowayprecision.com/smith...led-guide-rod-for-m-and-p-m2-compact-pistols/