Like most everything else, "serger thread" comes in a wide variety based on manufacturer. I've seen some from the "big box" stores that is very poor quality and I wouldn't use it even on my Serger. There is a lot of 100% cotton thread that I think is very poor quality and I won't use it.
I've been using Maxi-lock for my quilting for many years now, but I normally don't piece with it as I prefer a thinner thread for that.