I've given up on readymade bag mixes and started making my own. I order from
Orchid Supplies - Orchid Mix - Orchid Pots - Orchid Fertilizer - rePotme Orchid Supply, either individual ingredients (which I later mix as I want for individual plants) or they will make up a bag with my personal choice of mediums. Since I grow inside and out year round and have a variety of orchids, I really love having the flexibility and FUN of making my own mixes. It's not that expensive and I can order just what I need and I'm never stuck with too large of a bag of something I hate.