Personally, I try my best to stay away from the magnetic albums because of the glue. It's not that the sticky isn't Acid Free. It's just that the sticky was ... well, just too sticky. Supposing there comes a time when you want to remove them to scan them in somewhere, it could be difficult to remove, almost to the point where it'd tear the photos themselves.
I've seen it happen when I worked in a one hour photo lab, it wasn't pretty. The magnetic albums may be getting better now... But personally I'd perfer not to find out.
I usually am a pretty big fan of the albums that have actual sleeves of a specific size (usually the 4x6 ones). They may be less versatile with assorted photo sizes, but removing the print is as easy as sliding it out from the sleeve. The sleeves are usually Acid Free (also called Archival), so they won't do any undue damage to your prints as well.