I spent a good bit of money on a bunch of decent looking plants ... now I have none in there
He was smaller when I first put them in, and he was so scared, he didn't move from the middle bottom for a couple days. After a while, he started moving them around, tearing them up. The adolescent stage they can be quite a terror.
I might try again when I have a bigger tank and is a bit older and more docile

maybe not. Seems to like the open space now, and when younger seemed to like to hide a bit more.
If you are changing tanks, then you could always silicone the new plants in place ... but that is a little too permanent for me ... since I like to change it occassionally anyway.
The suction cup idea sounds like it would work ... though it doesn't stop the O from tearing the plant up (pulling pieces off). I guess it depends on how the plant is made