Before I got a rifled barrel I hunted with a set up very similar to yours (870 express with a rifled choke tube). To tell you the truth I have not noticed any difference with my fully rifled barrel--BUT I have not taken any shots over 60 yards with it. I suspect that at distances over that, its very possible the fully rifled barrel would begin to outperform the choke tube. Maybe some of the other posters can answer that question. On the loads, I found that the 2 3/4" Winchester 1 oz. sabots work very well for me...and I did not notice any advantage at all in using the 3" so I stayed with the 2 3/4" to save myself a little recoil. Every deer I ever shot with it went down like a piano got dropped on him. Bottom line is you have yourself a very effective and deadly weapon...probably to 75 yards at least and maybe beyond. Practice!