It's good PvP practice for free, yeah, and pretty early in the game. Also you don't have to waste Cracked Red Eye orbs, nor be human and risk being invaded yourself. Plus the game can summon two forest invaders to a fight, so you may have help.
The flip side is that some people wait there in human form with phantoms in tow to kill forest invaders specifically, so it's not going to be always easy. Especially if you're on the lower SL levels; you could be invading an SL125 guy with two phantoms lol.
Yes, I remember when first playing the game and joining the covenant and havng my ass handed to me time after time. Now that I am on NG++ I have rejoined the covenant and I am having a blast fighting these PVP forest stalkers.