Is the harborside resort a good place to stay at the atlantis bahamas?

I can’t say about this specific place because I’ve never been there, but there are many independent web-sites where you can read the opinions of travelers. Here is one link. Take any reviews for what they are worth…one person’s opinion. Rave reviews could be posted by the company; poor reviews could be posted due to a one-off situation, an employee of a competitive hotel, or someone overly obsessive.

As someone who used to be a hotel inspector and who has participated in a weekly beach house rental every year, I can tell you that most places won’t be as clean as a parent would want it to be, particularly at beach locations. The housekeeping staff has little time to properly clean between the change of guests.

Should i bring a pack n play? or should i use a crib there?

Check to see what they have to offer. There are enough cribs on the “unsafe” list that, If I were a parent, would want to know what they have. Also, there is no guarantee that they are cleaned properly between use. Often, they are just put back in storage. If you can arrange it, I’d take my own.