Ammo cans work great for my needs.
Particularly if you are going to acquire a Shield Plus. The new mags with very tight spring pressure are impossible to load by hand to full capacity.I pack my loose ammo into ammo cans (usually 750 in each can) when I go to train.
At the weekly IDPA training, and monthly IDPA matches; I put 200-300 loose rounds into a plastic ammo box that lives in my range bag.
It’s much quicker and easier to reload mags when you can grab the cartridges a handful at a time, instead of picking them out of their factory boxes one at a time.
Also; if you don’t own an UPLULA (mag loader), get one. They’re hands down the best mag loader that I’ve ever found. 👍