I received mine yesterday and it’s very nice. I ordered the memory-foam set and have been testing the various combinations that work for me. Just for reference, I’m a guy, average build, below average flexibility. Sitting in full lotus is definitely not an option without severe physical injury. What else? I’ve been meditating regularly for several years but I wouldn’t claim to be “experienced”. “Persistent”, maybe.
Here are some early thoughts about the Oasis. Comfort is subjective from person to person and even from day to day so I appreciate the ability to tweak the setup without needing to add/remove buckwheat hulls (although you can- there’s an internal zipper that makes it easy). The seat is comfortable to me. There are three inserts in the seat cushion - a traditional buckwheat cushion, a more firmly filled buckwheat cushion (for height, I believe), and a memory foam + coconut fiber top cushion. I’ve removed the firmer insert so I sit a little lower and softer. We’ll see if I change my mind later. The memory foam and coconut hull top cushion is comfy though not as thick as I had expected.- I’d guess that it’s about an inch thick in the middle? That’s actually plenty. I don’t really know what I was expecting, tbh. It was comfortable and stable to sit on, and that’s the important part. Don’t expect it to be like a memory foam mattress or something. 
The knee bolsters are nice and soft (full of kapok, I think?). It’s my first time using knee bolsters so I’ll need to experiment a bit to find postures that work for me (or not use them. Again, it’s nice to have options.).
The whole kit feels premium and it folds up nicely when not in use, which is great. My dogs may come to resent the loss of “their” cushion, however. The fabric is soft with a nice texture to it. It’s a pleasant neutral color pretty true to the pictures on product page.
I generally sit with my legs crossed, one leg on top of the other in an inflexible person’s half-lotus. One foot on top of the calf of the other leg. The bolster came in handy here to give some support to the top knee. I’ve gotten by without it for years, so it’ll take some getting used to, but it was a nice change. I briefly sat on my knees with a knee bolster directly under me stacked on top of the pillow (like in the pics on the product page). It worked. It’s not my usual way to sit and I didn’t try it for long but it seems like it would totally be comfortable enough for a long session. Sitting with my legs crossed at the ankles with a bolster under each knee worked well, too.
My first impression is very good and I’m happy with my purchase. If you’re just beginning your meditation practice you can’t go wrong (though it’ll probably spoil you). If you’re experienced with meditation you know how tricky it can be when your cushion is not very comfortable (yes, we learn how to “work with it” but…) so maybe consider the Oasis when you’re ready for an upgrade.
I’ll post this as a “proper” review on the store, but figured I’d post on the forum in case folks were interested or had questions. 