I have 100 and 144. I do tend to like 100 better, but it’s not something I lock myself into. Depends on my budget, free space, gumption, and the model itself.
As far as moving with gunpla, no, but I have moved with minis from Warhammer and such and have had no issues as long as I used good carrying cases. Maybe try some rubbermaid containers and pluck foam?