It depends how heavy a load you shoot and what shot size. If you look at the Kick's chokes website it suggests different constrictions for different loads. I use 3.5" Hevi shot magnum blend with a .665" Carlson's choke in my SPR 453 and a Cabela's brand .670 dia choke with Hevi 13 3" 6 shot in my 870.
I think most of the chokes out there are pretty good with most loads. If you really want to know you have to pattern your gun with a bunch of different load/choke combos.
There are a ton of great chokes out there, I don't think you can say which is best, it is just personal preference. I get great patterns with my Carlson's and it cost less than $40. There are $100 chokes out there too. Comes down to how much you want to spend and what you want out of it.
To kill a tom at 40-50 yards I think most of the tubes on the market and some Hevi 13 6's will kill em. I really like the Hevi 13 for the patterns, but you certainly don't need it. I used lead 5's for years with good sucess.
The federal loads with the flitecontrol wad shoot good out of most factory full choke tubes from what I read. They don't need a lot of choke like conventional loads do.
