The Bersa Firestorm .380 does not have the lock. Some of the earlier Thunders apparently did come out without the lock, but I don't know the date. My wife bought hers late 2007 or maybe 2008 & it has it.
I have the Bersa .380 Plus & it has cycled anything I loaded in it, including Federal HST, 124 & 147 gr. HPs. It is in my carry rotation. Took it to a 'Meet & Greet' on another forum & a couple of the guys shot it. Thought I was gonna hafta fight them to get it back!

They both have bought one.
My wife & I have several Bersas, among them, Thunder .380, (2) CC .380s, Thunder Plus, .380 Combat & Firestorm .380 & the locks on the THunders have never been turned on. I suppose the keys are still in the boxes & never a problem with any of them. Nor have I heard of anyone having an issue with them locking accidentally.