We did 2 excursions in Bar Harbor, worked out fine, but we did worry a little at first. Tried to do two in Nassau, but the 2nd got rained out. Depends on how stressed you want to be. Talk to the shore excursions personnel, they'll tell you if you have time for both. Yes, they're trying to get money out of you, but the workers we talked to were honest and told us if we could or should do 2.