Anyone have experience with a Remington SP-10 semi auto magnum shotgun? Opinions?

No, I actually enjoy eating my birds.

what?

I have owned and hunted with an Ithaca Mag-10 for several years. The Remington SP-10 was based on the Mag 10 after Remington aquired the Ithaca patent. Though parts are not interchangeable, they are pretty much the same gun/design. As well I hunted with a Browning Gold 10 last year.

What are you wanting to know?

I want to know if the gun performs well. I use a 20 ga for dove & quail, but a friend wants to sell his Rem 10ga and I will also be hunting geese this year.
It may be too much gun for most hunting.
You can't kill anything deader than dead.

It should if it has been taken care of. It is heavy and it is a gas gun. You will have little recoil compared to a lighter 12 GA gun with magnum loads. Though Remington made some improvements on the Ithaca it was copied from, I am sure it must be kept clean to reliably function same as was the case with the Ithaca Mag 10. They have been making this gun for several years and it has a cult following. Some may like the browning better, but some like the Remington better.

For factory loads, they are not the cannons people make them out to be. As I posted in another thread recently there are fewer factory load options than there used to be and many brand name 12 3.5" loads compared to same load in 10 GA actually offer a greater fps or payload in the 12 offering. An example.

Winchester Supreme
10 GA, 1 3/8 oz #2 shot, 1450 fps.
12 GA 3.5", 1 1/2 oz #2 shot, 1475 fps.

So unless one reloads, a 12 3.5 mag shotgun would be the smarter buy. For factory loads even for goose hunting, your not gaining enough added range or payload to matter and ammo is more expensive. Also ammo is pretty much a mail order thing. But if your getting a great deal on the 10, it may outweigh the ammo issues. One thing that can be a benefit is better patterns with the greater bore diameter, but then again consider some factory 12 GA guns are backbored these days.

I use mine for a lot of general waterfowl, not just goose hunting. My loads are often of a smaller payload but of a faster fps than the guy next to me shooting a 12 GA. But I reload.

And I do want to stress again on your question of performing well. Only if you keep it clean.