Our success rate for spring and fall are pretty much the same. We hunt bears a little differently in the fall sometimes. We set out baits but we also have a lot of agricultural land to hunt and may spot and stalk as well - especially with firearms hunters. In the spring, you may have the opportunity to fish as well.
We still have openings for next spring or fall, (just over 1/2 full) but the earlier you book, the more selection you will have for dates.
As for caliber, we recommend a minimum of a .270 with a heavy, well constructed bullet. Most whitetail rifles will get the job done. Most shots will be less than 100 yards. The guns you mentioned will all work. All our bait sites are setup with the bowhunter in mind.
As far as specific equipment, the first thing that comes to mind is a Thermacell. You will see a list of specific items to bring on our website.
Let me know if you need any other info,