IBM

Lots of learning resources. Great culture for constant self-improvement. IBMers really help other IBMers succeed.

Layoffs are more frequent than you would like them to be. Valuable peers will be let go, then you will see a new team get created and you wonder why they could not just reassign your peers to the new team.

In many sites, promotions can take forever. To get promoted, you better be ready to look at a different company.

If you stay there long enough, you may end up with a mindset that everything is better at IBM, limiting your chances to move out quickly if you get laid off.