Which side chain should I move my eth onto?

I’m moving all my eth off exchanges and Crypto.com allows transferring using an L2. Stupid question but are there any pros or cons to using Polygon or Optimism?

Do they just work exactly the same as if it were on the main chain? Are there any risks to leaving it sitting on polygon network as opposed to the main chain?

Is using the bridges 100% reliable if I ever wanted to move between chains?