It boils down to a matter of what you feel comfortable with. I would like to know what people are considering a long barrel? Personally I consider anything over 30" long, but others may differ. I shoot a 3.5" Browning BPS with a 28" barrel and a 2" extended choke tube. The difference in velocity between my 28" barrel BPS and a 24" barrel BPS may be marginal but the difference is there. Another difference, my longer barrel does shoot a better pattern than the 24" barrel BPS shotguns. I have seen this with my own eyes and I have friends who own the 24" BPS shotguns and as much as they try when patterning our guns, they can not put as many pellets in the target as I can. Sometimes the differnce has only been 5 or 10 pellets but other times it has been as much as 35 and 40 pellets. I can' t speak for other brands of shotguns but I would imagine that any brand of shotgun would have similar results.

Shoot both the 26" barrel and the 30" barrel and see what you like the best and which patterns the best.