Good choice, Renegade. A coupla things.....
Any compromise setup like these combos will not perform in a certain mission as well as a dedicated and specialized one. However, humans are adaptable. We can work with a non optimal shotgun/load/choke and make it do the job. Shotguns are generally pretty adaptable also. A decent repeater can work in duck blind, on hardwood ridge or for WWIV with but a few changes.
An 870 with two barrels, a couple of chokes and plenty of ammo is as versatile as a mechanic's toolboz.
For any facet of shotgunning the first step is basic proficiency. Learn your tool. Buy the lightest loads you can find. Using good form as outlined in the 101 threads, use them up while learning how to load, unload, make safe, make ready to fire, fire, etc, all in the safest manner.
Shoot it,get more ammo, keep going until it feels like a body part. Lessons from a good instructor will speed things up greatly.
HTH....