The stock L plate bridge allows too much lateral movement of the string saddles, it won't maintain it's adjustment without some sort of thread locker, and even with nail polish or loctite to keep the height screws in place, it still relies on string tension to maintain intonation. add to that the current version of the L plate with it's single string slot not being lined up with the pup pole pieces, requiring either replacement of the bridge saddles with the more popular (and functional) threaded bar type saddle, or compromise in string position relative to pickup pole location.
And while it's really not an issue for all L plates, the so called "vintage" plates with the slotted screw height adjusters rather the a hex drive screw, are stupidity for the sake of vanity. Why would anyone want to suffer through the slotted screw nightmare just to look like they have an old bass when the parts are in fact repop rather than OEM? You are not adding a penny's worth of value with the slotted look, and you are opening yourself up to much greater potential for a slip and scratch in the finish from a flat blade screwdriver, something that's virtually impossible with a hex drive.
Other than the above, and the stock L plate, or any bridge that fails to lock in the saddle lateral position for that matter, not working with my playing style, I can't think of single reason to not like the stock L plate.
Oh wait, there is also the (very highly subjective) differences in tone and sustain attributed to various styles of bridges to endlessly argue, which insures this topic will never go away so long as TB exists as an open discussion forum.