I went ahead and got some catless downpipes from AR Design for my F10 550 N63 and will be installing them on Friday along with Meisterschaft mufflers and mid X pipe from the secondary cats back.

I know the CEL will pop on my dash from the catless DP's while I wait for a tuning company to release a tune for the F10 with a rear 02 sensor delete, and I'm ok rolling with the CEL on for a few weeks/months

However, are there any side effects from the CEL being on, other than being annoying every time you look at it?

Thank in advance for your input.

Lui