Most IT places which delete mail after a certain time do it for good reason and archiving your mail may be forbidden as well, better check first.
OK, Outlook Issues, I've worked with it since OL97 in both a support and user role:
#1, everything isn't in the same place. You have t look in the calendar for appointments, the tasks for todo's then in the journal for other things, then if you want reminded of a simple birthday you have look in the contacts or set a reminder manually as there isn't much integration between the parts of it. You can get kind of a big picture of part of your data on the outlook today but not all of it.
#2, is the use of the PST for data store for most of it (if your not on an exchange server), though in new versions you can use ical. The PST is a huge database file which likes to get corrupt easily and you can't make backups without closing outlook first because its locked for writing all the time. Run scanpst often and make backups often. Then if your on an older version you have to archive to keep the pst from hitting the 2G limit and with newer versions you still want to keep it smaller than 2G anyway. then comes the problem of opening those archives, sometimes one gets stuck open and other times mail sorting rules send your mail to the wrong .pst file even if you don't have it open.
#3, you will need serveral third party plugins to get some of the basic functions that are found in decent mail programs then your Av program will have to understand outlook macro virus as well.
#4, too high of cost, if OL could be bought for under $50 it might be worth it but a real license is around $100 or pay hundreds for the whole office suite with more buggy programs.

yes OL looks nice and has a lot of nice feastures, but once you get to power user status you start to find a lot of issues, bugs that have been there through many versions which never got fixed, badly thought out workflow issues, etc.