Congrats on you 910!!
I have a blue early production 910. Fine pistol which served me well for almost two decades now.
As near as I can tell, having lost my log books during a divorce back in 2007, my 910 has over 20,000 rounds through it. Most of those rounds were run through it before I had any experience with semi auto pistols. IE I didn't know about proper lubrication of an aluminum frame or the value of replacing recoil springs at proper intervals.
So I ran it around 9 or 10 thousand rounds on the original recoil spring. Only lubed it with Breakfree too. Gun functioned perfectly and ran well. No malfunctions.
Then I read on this board about improving the accuracy of my gun by putting a steel guide rod from a 5906 in it. So I did that too. I saw very little......if any, improvement in accuracy and within a few thousand more rounds I cracked a frame rail.
So, did my lack of proper maintenance combined with hard use cause the crack? Or did the installation of the steel guide rod combined with the inadvertant abuse break the camels back? Your guess is as good as mine.
Funny you mention replacing the barrel. Around 2005 or 2006 my 910 started shooting patterns rather than groups. My gunsmith examined it and told me that I had very little rifling in the barrel. He said it was etching rather than rifling. He thought that it was a defective barrel as I had not shot enough ammo to shoot the bore smooth. He replaced the barrel and the gun went back to shooting as it had.
I use Mecgar magazines when I'm not using factory OEM mags. All S&W 9mm high cap mags will fit and function in your 910. I used a Pro mag one time and consider them to be junk, IMO. I would never advise their purchase or use.
I advise you to shoot your 910 with the original guide rod. Mine functioned fine and while the tip of the plastic rod got a little chewed up, it never effected function or failed to work as advertised. Had I to do over again I would not put the steel guide rod in. It did nothing for function and little if anything to the 910's accuracy.
I still occasionally shoot mine as the hairline fracture doesn't affect the function or safety of the pistol. I still enjoy shooting it.
My experience with the 910 for what its worth. Hope it helps.
Enjoy that fine 9mm! The 910 always struck me as "looking like a semi auto should". Nice pistol. Regards 18DAI