What you can get with the Polywads is something of a "donut" effect:  weak center.  You can usually solve that if you reload by either modifying the disc or else dropping a layer of shot on top of the disc.  But I agree that they're a very short range load.  Cylinder certainly limits your effective range, but patterns tend to be very even.  Matter of fact, the guys who wrote the pattern analysis book (doing a brain dump on their names) said that you get more even patterns with no constriction than you do with any degree of choke. 
Interesting about the shot used on top of the insert, I haven't tried that.  As well as the insert modification.  What type of modification?
I usually put a Spreader in the right barrel when hunting over my dogs.  From what I've read, they don't widen the actual pattern, but disperse the shot throughout the pattern earlier, "Spreading" out the shot stream.
Anyone pattern any loads with these modifications?
Regards
Ken