My husband and I are planning a cruise to Alaska this summer for our 25th anniversary. So far, I am considering Celebrity's Infinity. Has anyone been on it? Any comments about this or any other Alaska cruise we ought to consider? (or not consider???)

I also would love to hear about the extra excursions that are recommended... and do you think that it is safe to buy the excursions from local companies instead of the cruise line. I know they are much cheaper. Are they safe? Are they comparable?

Thanks, Diane