Kabuki Springs is an SF institution and is a very nice place, but it can also be too crowded sometimes. Imperial Spa in my opinion is a great alterantive. It is a Korean style spa, which means it had a hot pool with a separate cold plunge pool, a steam room with herbs, a sauna and shower areas (also has the sitting-down bathing area you find in Asian spas), and wheelchair accessible areas. The men's area is separate from the women's section. It's very quiet, nice skylight and virtually nobody else when I was there. I'll definitely go back because it's so rare to find such a clean, non-crowded area in SF these days. They also have acupuncture and massage services but I haven't tried them yet.
Pros: No crowds, nice skylight, separate men's and women's section means it's open all the time
Cons: Less space vs. kabuki
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