I have a G30sf converted to 10mm. I did put a 21lb spring but see or feel no difference. The 45 and 10mm use the same spring on Gen3 guns
My conversion has been 100 percent reliable. I have a gen 4 27 and it has a different feel than the gen 3. I noticed that same thing with a G21 in Gen3 and 4
I use gen 3 mags in my gen 4 with no issues. The only thing is you wont be able to change mag release to left handed user side.

Ive been hand loading for 30 years and have never seen a kaboom but this looks like the result of an over worked case. It probably had a crack in it
prior to loading.