I’ve seen one, and possibly two, carbines in my courses that had malfunctions caused by the addition of a BAD lever. Doesn’t mean you’ll have one, but it happens.
I sent a round into a barricade with the bad lever. Used it to drop the bolt after a reload, finger rode right off the lever onto the geissele trigger and bang. My shooting family along with myself got rid of all of them after that, figuring there was never need to be in a hurry to lock the bolt back save a malfunction.