Unless you are shooting 60 yard targets, full is too much. using a more open choke and smaller shot will net more hits.
Extended chokes (good ones) have several advantages.
1) the additional length allows for a lower angle on the constriction which tightens groups.
2) the additional length allows a parallel section at the end which further tightens patterns as well.
Porting looks fancy but does nothing positive or negative.
Try a Trulock choke. They are some of the best out there and are quite reasonably priced.
http://www.trulockchokes.com
A good choke is well worth its price, pattern your current chokes first to see if you have any holes and see what the true performance of what you have is first, you may be surprised but will likely do better with a good aftermarket choke.