It should be a 1:30

That length barrel in that twist makes no sense to me on a ghost

Cons:
- More hold sensitive vs the 23", (read: it will NOT be more accurate)
- overall longer gun
- will gain more speed for pellets, which you don't want or need.
-Has the power to shoot slugs, but they won't group.
-Barrel harmonics come into play more so in a 28inch barrel.
Pros:
-Gain shots per fill as you can turn reg down to get the correct speed for pellets.
-Once tuned down it should give a gentler shot cycle.
Will be interested in seeing your results though vs your slug barrel! Maybe do a 50& 100Y competition between the two!?