I've bedded a bunch of them as well. Creating mechanical lock is a must-do and I've heard everything from cleaning with acetone to using a soldering iron to roughen the surface, I've tried it all, it all worked the same, which is to say: it all worked well.
You can stiffen the front end by filling it up the hollow area in the fore-end with marine-tex. I have only done this once, on a Remington plastic stock, but it went from very wobbly to pretty stiff. I also stuck a carbon fiber arrow shaft in there but I am not sure it actually did anything.
Long story short: I would not hesitate to bed your plastic stock.
