Yes it's "safe" in the sense that it won't blow up your pistol. However use of +P loads should be limited to once in awhile. Steady use WILL shorten the life of the gun. I personally think there is very little to be gained with +P loads over standard loads. Where you hit them is far more important than what you hit them with. I have seen a number of guns that were totally abused and ruined by the use of hot loads. Better to invest in extra recoil and firing pin springs for your gun to ensure positive operation and long life. Don't buy into the snake oil from the ammo companies.
If you are going to shoot a hot load out of your 1911, invest in a heavier recoil spring, (weights go all the way up to 22 pounds) and a recoil buffer.
You may have to buy a couple to make sure that you don't go so heavy that you will not cycle completely.
Should be more than a few vendors carrying some at the next 1500 in 3 weeks.
My dad's old AMT Hardballer had a 21 pound and a buffer and he put 1000's of 230gr +p CorBon's down the pipe with no problems.
It will help protect your investment with a small price to pay.
SA tends to spring their guns a little on the light side. You can fire your Hornady stuff, but be aware of potential long term damage with the current recoil spring. I would suggest you go to Wolff gunspring's site, get their 18.5# recoil guide spring. This will not only protect your gun, but also add to reliability. Weak recoil springs will make the gun function funky and slow, FTF almost ensured.
All in all, the Loaded is a durable gun, fire away, but take precaution. It isnt going to wear out in 100 rounds or complode in your hand, but it will potentially cause damage with long term usage without the appropriate spring. IndyGunWorks has it right: +P in .45 is cool, but really adds little to the great performance of .45 hollow points. All it would do is add some controllability issues potentially. There are many MANY standard pressure HP available out there that would have similar, if not better success in your .45.
Plus P will not hurt that pistol. You'll want to watch it in aluminum framed pistols, but I don't believe yours is aluminum.
I prefer to take the recoil spring up to 18lbs or so, and the mainspring down to 21lbs (stock is 16lbs and 23lbs, respectively).
You really don't need a shock buff. If you decide to get one, however, make sure your pistol runs 100% with it installed - many do not - and check it often for wear.
Overall though, it shouldn't hurt your gun at all to fire it with +P stock. I'd be more concerned about the slide velocity outrunning the magazine spring.
The 1911 is designed to function with 230gn at 850fps. If you vary too much from that, you might start having problems.
Thanks guys, I just wanted to put 4 rds down the barrel and leave the rest for carry ammo. I hardly ever plan on using it...I hope. The only reason I picked up +P is because I couldn't find any standard loads and didn't want to carry FMJ.