Well, it has been quite a while since I opened this thread, and I should tell 'the rest of the story'.
I decided to go with Hans Vang at Vang Comp Systems ( www.vangcomp.com/
- great web site, by the way), and he worked over my 870 Express Super Magnum as well as my son's. SureFire fore-end (618F), 18" ported barrel, MMC sights with tritium front, magazine extension, big head safety, high-visibility (green) magazine follower, side saddle, Giles sling. Hans definitely does everything SCT does, and more. He got the gun back to me 2 weeks early. Everything worked perfectly right out of the chute. The tritium front sight is impressive.
I took a Gunsite Tactical Shotgun course last weekend. Even with my old eyes I was able to impress the younger guys - those MMC sights really helped me sight in with slugs. The porting clearly reduced the recoil. I've practiced with the very 'low ready' position (barrel nearly on the thigh) Gunsite recommends for searching a structure / house, and it is clear the SureFire light could be used to illuminate a room without directly pointing the muzzle at 'non-targets', to put it delicately.
The only problem I had was the side saddle loosened up, and I lost 3 screws out of 6. Today Hans said he send out 6 more, and I'll Loctite them in. Note that nearly everyone else in the class had the same problem - we ran over 300 rounds through these shotguns in 2 days. This blip didn't faze me.
A BATF officer (a fellow student, and a very decent guy) was by my side most of the class. His home defense shotgun had only a bead sight. Our last slug exercise was from 100 yards, and to get on paper he had to aim nearly a foot over and to the right of his target just to get on the paper. Not to get COM, mind you - just to get on paper. With the MMC sights I had no such problem.
The patterns were as solid / small as noted above in other posts. And, slug performance was consistent and tight. I'll head back to the range in the next few weekends to put the guns on bags, sight them in once again at 50 yards, and make sure they're as perfect as I can get them.
By the end of the class I was absolutely sure I'd made the right investment.
Now, I'm not a magazine writer, so I can't literally compare SCT and VCS work (or others, for that matter). However, my shotgun is absolutely fantastic. I have 100% confidence that if I had a problem Hans would fix it. And, any excuse to talk with Hans again would be fine by me - I don't think I've met a nicer fellow in the firearms industry. He also holds the patent for his technique, and it appears his process is being copied by others. They do say imitation is the sincerest form of flattery.
I want to say thanks again to all of the TFL members who gave me feedback in this thread, other threads and by email. You saved me a lot of aggravation, and helped me make a fun and practical investment. Thank you.
Regards from AZ.
[This message has been edited by Jeff Thomas (edited May 06, 1999).]