I am going to purchase a Wolff "dual assembly" recoil spring/guide rod for a Glock 30 in 45 acp. They are available in 17 lbs, 19 lbs, and 21 lbs. Though I like the 21 pounder I have used in a Glock 29, I have ruled this one out. So what I want to know is, FOR A DEFENSIVE CCW WEAPON, where ultimate in reliability is the overriding factor to the detriment of all others, is the 17 lbs or the 19 lbs the best one? I should tell you that I keep a +P in the pipe, and one more +P HP to top the mag, then a mag full of NON +P ball ammo, so it needs to function reliably with the non +P pressures, too. I'm guessing that the obvious answer is the 17 lbs over the 19 lbs for CCW, but since I WANT the 19 to reduce the pounding on the gun, I was hoping someone could justify it for me with an anecdote of utter reliability in this pistol with this assembly. Oh, and I think the factory single assembly springs are 18 lbs, IINM. TIA.