I'm in NY, and I've been growing my inaugural two in the window that gets full sun in the morning, in sphag, which I keep constantly damp. I didn't put Osmocote in the pots, so I'm having to mix up fertilizer each time I water, and I won't do that again next year. Keeping them this damp feels weird, but they are growing like crazy.

If you're in a place with high humidity or a lot of rain, or can get out to water them every day, I know people do grow them happily in LECA. Regardless of what you choose: these orchids do a ton of growing all at once, they put out a ton of roots in a short period of time, and as a result they need A LOT of feeding and a A LOT of watering. If you keep on top of that, it probably doesn't matter what you put them in.