I've been making the 5-1-1 container mix aka Tapla Al's for years now and it works great. I'm too lazy to do the screening part, but try to look for good sized bark to use. Some years it is harder than others to find it. A bale of peat moss, a 4cf bag of coarse perlite, fertilizer, and a bag of garden lime last a long time. I just need to buy pine bark most years. Much cheaper than any commercial mix, and the plants are much healthier. You need to water more regularily than with those "moisture mixes", but you won't have the root rot and stunted growth that you often have with those. Similar high quality commercial mixes are available at nurseries, but are very pricey here.
For starting seeds with wintersowing I use regular potting mix though, preferably compressed bales of ProMix when on sale. The 5-1-1 isn't good for seed starting. It stays so loose that it falls away from the roots of seedlings at transplant time.
