A lot of people use it with great results. I have most of my trees in DE right now. For conifers I’ve been doing 1:1 DE to perlite. They’re doing great. Ive started using more a 2:1 DE to perlite for my deciduous. Though I have some deciduous in 100% DE and they’re growing well too. The DE I use is Optisorb. It has a larger average particle size than the Napa bags I’ve bought. Though I still use Napa for shohins because the smaller particles are great for that use. I have a shohin Spirea in 100% Napa 8822 and it is growing beautifully.
There is a lot to show in the bonsai world that supports DE as a fantastic soil component. Well renowned European Bonsai artists have been using DE for decades. There’s a brand of kitty litter they use over there that is 100% DE. They were widely using DE in Europe for bonsai before it caught on in The USA. Hope that helps!