Both - plastic is my preference for water, or wet conditions and dries quickly. Variety of sizes and colors, orange is great for blind work, etc., flasher black and white, white are easy to see in different lighting conditions. Canvas because it can be scented with bird scent and great for land work, and different sizes.
Cons for plastic would be doesn't scent well, cheaper bumpers can crack/break in cold conditions. Cons for canvas would be limited on color choices, gets stinky if not taken care of when wet. Can be hard to find; can be pricey.
I have a dozen or more of each: canvas and plastic. Some I've had for 8-10 years because I use them exclusively for training. Dokken's are nice but pricey too, I've got a couple of them that are old too.
I prefer plastic. Don't soak up water and white canvas ends up dark brown in a few days. I do use canvas for some puppy stuff.
I just ordered some DT systems soft-mouth dummies and really like them. They are soft and pliable even when cold. The last N&B I bought, the pastic was hard, brittle and several cracked. Also, several of the valves fell out within a few days. I like the basic Lucky Dog dummies but have lost several valves from those as well.
I use both-plus Dokken's birds pheasant- goose-duck for a lot of blinds and water work-they are good- some of mine are 7-8yrs old gertting a bit worn and tough to dry-canvas seemed to be preferred by my dogs- Lucky dog plastic can be thrown farther and dry easier dogs like them ok but newer Avery Hex bumpers are hard and dogs do not like them much at all- also use launcher bumpers in canvas not a durable as some( ends blow out with heavy charges) of the egg shaped plastics- all in all, different materials/ styles all seem to have their place and now with only 2 dogs it seems like maybe I'm over bumpered-if possible?
Plastic- 12 ea orange and white-Dokken's 8 dux- 1 goose- 6 pheasant-canvas- 8 launcher bumpers- 6 canvas and 2 eggs-BL & White's 8-Misc-Avery- 4-
Thank you everyone Iam going to go with a mixed bag this Friday so I can start training more with the puppy and her mom. Its nice to see the pros and cons of each to beable to determine what works best for the scenario.