I've garnered some new parts for several guns and tried them out at the range last week. Thought I would post my experiences and impressions:
1) Springfield XDm-9 4.5" 9mm - Solid Steel Guide Rod: I decided to order some extra recoil springs for all of my guns and while I was at it I found Wolff had solid steel guide rods for this gun in addition to their recoil springs. This is a Home Defense gun and is never carried, so the extra weight isn't a problem. The premise is the extra weight placed towards the muzzle reduces felt recoil and muzzle flip. And to me it just seems more durable than the hollow one from factory. I installed it and the results were a noticeable increase in weight but it seemed well balanced. Recoil and muzzle flip were indeed reduced (it was very light to begin with) and it did make it easier to get follow-up shots on target quicker. So the change definitely did accomplish the goal.
2) Taurus PT709 - recoil spring assembly: After 4200 trouble free rounds, the recoil spring assembly broke. They are on backorder with Taurus. I found a new blued PT709 on gunbroker for $200 and bought it since I like my SS one so much. Figured an extra for that price just makes sense. I shot the new one and other than having to adjust the sights in it was flawless. I put the recoil spring assembly from it in my old one and it shot flawless as well. I have my old one dialed in to where I can shoot the center dot out of a shoot-n-see target with one mag from 15 yards, so I just left the new spring in my old gun and will replace the spring in the new one when they come in. I'm going to have several spring assemblies on hand and change them out about 3500 rounds going forward.
3) Taurus TCP 738 - extended 10 round mag from Pro Mag: The mag released after every round. One shot and it would release enough not to chamber the next round every time. I messed with it a while after the range session and it just won't get a good positive lock in the mag well. It snaps in, but can just be pulled out by hand with not much effort. This is junk and will be going in the trash.
I also spent some time shooting my Kimber 1911 9mm. Nothing new with it, just a pleasure to shoot and I always make time for enjoying it at the range.