Welcome. It's good to see you here. As far as I can tell, I've shot most if not all the commercially available 20 gauge choke tubes. It's been a "project" since about 2000. At that time, there was not much variety in either chokes or shotshells.
When Remington Hevi-Shot came along that really helped to improve the 20's performance. The Rhino was about the best 20 gauge choke tube, in my experience, at that time. We introduced the Swarm 20 gauge turkey choke just as E-M introduced 20 gauge Hevi-13 and were fortunate enough to set a couple of still target shooting world records and win a world championship with that design.
Today, there are other good 20 gauge turkey chokes on the market and a variety of good 20 gauge turkey loads. You may want to read the results of my tests last year of all the 20 gauge loads and chokes at http://www.allaboutshooting.com
The article is entitled "20 Gauge Shotshell & Choke Test" .
I have been shooting the new 20 gauge Federal Flitecontrol Wad shells for the last month or so. I started with the #5 lead shot loads and have been very impressed with their performance. I usually find that #6 shot patterns much better than #5 shot, regardless of the gauge but this #5 shot is really patterning much better than the Federal #6 lead shot that I shot last year. The numbers are equal to some of the "hard" shot that you'll see in that article.
Federal has learned a lot about the Flitecontrol Wad in the past 5 years. I've shot hundreds and hundreds of the 12 gauge shells with that wad since late 2004 and it required the correct type of choke to optimize its performance. The 20's shoot well through most chokes, better in some than others but overall do an excellent job.
Hopefully, I'll complete my work with the Heavyweight shells in a bit and be able to publish my completed work on these shells on the site.
The lead shells and the #6 Heavyweight shells have been shipped to distributors and the #7 shotshells should go out in a couple of weeks. You may want to check with your retailers about them now. Some are keeping a list or allowing backorders.