Has anyone purchased a companion from the Zen store?

Just wondering if any companions I buy from the Zen store are assigned to the character I'm playing when I buy them, or I can use that companion with any of the characters on my account.

Or if I should be smart and just wait till level 16 to get a free companion...

They are locked to your character. Really not worth getting them. The only good ones at end game are the zen cat and the ioun stone. They do nothing but give you stat bonuses.

While leveling, the cleric is your go to.

Also coming in the first Module (aka Patch), you will be able to buy training books for your generic companions with AD. This will allow them to level up more.

They aren't locked on your character (unless it changed), they're locked TO a character.

Difference being that you can trade them between characters, which is a value add.