I'm sure you will like it. And for that price I'd probably buy it and keep it even if it didn't fit the horse you will get, it might fit one later on. I've riden in a few other brands on trails and I will say I like the simco best and not just because it is mine lol. It puts my legs in a better position and I like how the barrel seat hugs my butt.
Raigen- I'd say It'd be just fine for trails! Most trails saddles just have "fancy" seats, usually gel, plush or something else and extra ties to attach bags or store things. Nothing too special about them. I trail ride in a barrel saddle, it's comfy for me and I know many others who do too. The seat covers I LOVE, it keeps my legs and rear warm in the winter and from getting to sore. They tend to range from about $30 - over $200 depending what brand / thickness / material ETC. If you're a serious trail rider, or don't like getting sore I would definitley have one.
This one is actually made by the company that makes Impact Gel pads, it's around $130.