The SM150 L Cup has been a real pleasure to own and I'll definitely get another if anything ever happens to it. Here's some commentary on different aspects of the doll:

Breasts: The breasts are even better in person and I'm glad I got them gel filled as I think that feels better than the hollow kind. If I ever do have a relationship with a real woman again, I'll honestly always miss the sheer volume of these things. I've always wanted this kind of thing and now that I got to experience it, I'm spoiled for life.
Feel of material: It's very soft, so much that if I use it for a week and then swap it with a silicone doll, the silicone one feels too firm.
Oral: The mouth has good suction and even though it's not the best, I'd much rather have a good mouth in a head that I can use without worry than an excellent one that costs twice as much and starts to lose its carefully painted lipstick after a few uses.
Vagina: It feels extremely soft and not overstimulating as is a common thing with dolls. As the material has more give than silicone, it also has a more narrow opening that seems to clean and dry more easily. I've never had a doll with an insert, so I can't comment on how that feels or washes out.
Weight: Very good when compared to dolls of similar bust size. I just browsed some other huge boobs types and this doll weighs significantly less than pretty much everything its own height and larger.

This doll is pretty much the only one like it. As someone who considers skinny women with enormous breasts ideal, this doll is almost alone in providing that aesthetic. Other dolls that get close often have serious drawbacks that this one doesn't. The competition either weighs more than I think they should, are too tall (making them even heavier), are fat from the waist down (people call it thick , but I just see obesity) or some other issue.