I'll go on a topsoil kind of rant for you, lol. I've been in the landscape world most of my life, I'm 59 now. ANY mixed bulk "topsoil" is junk. They usually mix local fill dirt with sand and some type of organic material which may or may not be composted. Organic matter that's not composted eats nitrogen, therefore starving the plant of a much needed nutrient. Sand just sucks unless you have sand as your base soil anyway and then you don't need more sand. Sand mixed with clay takes on properties that doesn't resemble good characteristics of sand nor clay.
In My Opinion I think your best bet is a screened local soil that YOU incorporate composted organic material and then even some mushroom compost or composted manure, either cow or chicken, but it's got to be well composted or the cow will grow weeds and the chicken will burn. Your sawdust will be a barely composed carbon that will need a lot of nitrogen so it can break down so the plants can utilize it.
None of this is any good with out a soil test to see what pH and other needs this Topsoil may need. It's not rocket science but it is science and soil tests are easy and cheap.
BUT people want what they want and sometimes you have to give them that and move on... Buy them a $500 load of "topsoil", do the job, and move on.
And yes Wallace Farms is legit, they have good product.
