Both boats are nice boats and I have fished on both at one time or another. Pursuit has been around a lot longer than Carolina if that means anything to you, but you may already know that.
Cummins is a good engine. I used a Cummins 370 hp in-line six cylinder (883 cid) in my tractor trailer and with the same gearing could stay with the Cats no problem. THe Cats are also good engines, but the Cummins people weren't as proud of the parts as Cummins and therefore Cummins was less expensive to maintain.
Had the pleasure of fishing both a number of times, the carolina (28) was a better riding unit in the rough stuff, the pursuit was was a better drift riding unit, the range on the 30 offshore with the power you are considering might be a issue. Both are same quality construction in my eyes. If I had the choice and range is not a issue in my case the 30 offshore would be in my slip.