go for it....I fish both and they both have different good qualities......
I would probably get the glacier bay with a full vinyl enclosure, it rides alot smoother in the rough stuff that we have alot of most of the year.
The world cat is a great boat, it is drier than a glacier bay and faster but it pounds a little more and is a little bit rougher ride in our average conditions..... DO NOT get a world cat 266 with anything less than 200 hp twins on it. I dont care what you think you can get by with, 130s or 150s are way to small.....175s are borderline.....200s perfect, anything more is a bonus.....
as far as swell vs chop, cats ride great in either condition, mono hulls are just faster in swell because you can put the pegs down a little more....
with either of these cats you will be passing up the sportfishers in 3-5' seas and you will be doing it fairly comfortably.....