No one will be able to give you an accurate answer to this. Period.
It depends on a few factors:
1) How long have you had your pleco?
2) How big is the tank?
3) How many different hiding places?
4) Luck.
I've had my L200 for 5 years now. About 2 years ago, I put in a Planiloricaria cryptodon (Spoonbill Whiptail Cat). This catfish wasn't even technically a "pleco". He was absolutely destroyed by the L200 in less than a month. Lights on, things were fine. Right after lights off, he beat him up routinely.
Once plecos get settled into their territory, that's it. I tried moving hideouts around, switching around the tank, etc.
Your best bet to house plecos together in harmony is add them at the same time, provide multiple hideouts, and pray. Some people succeed, some don't. I can tell you one thing, I've encountered some really bad attitude royals in my day. One specimen would attempt to "club" anything that entered its territory with its cactus like pec fins.