I haven't actually used bamboo fabric all that much, except in modern cloth nappies, when I was making them for my sister's babies. In that instance, I was using bamboo fleece from a dedicated MCN fabric seller, and I found it to be fantastic, with good wear, absorbency and easy to sew. I have purchased bamboo knickers (my homemade knickers are based on purchased Jockey ones) and found the fabric stretched out and wore out very quickly. But, that may be an indication of the quality of the fabric, and the lack of spandex in the fabric.
In the past I have linked to the Bamboo Fabric Store here in Australia, mainly because they make some fairly good looking ecological and ethical claims around the manufacture of their fabrics. I think the last time I purchased from them was quite a few years ago, so I would recommend that you research a bit yourself, perhaps with an email to the store you choose, asking about their manufacturing process and suppliers. I can't provide a direct recommendation on the fabrics, although you have reminded me that maybe I need to consider them again.
I feel (and this is in no way an opinion based on fact) that where the source materials are grown ecologically, that the production process can't be any more chemical based than any other fabric. I do know that cotton requires a very large amount of water, both in its growing and processing, but I have no idea if the same is true for bamboo. One of the reasons I have pointed to the store in Australia, is that our consumer laws are such that if they make claims, they are required to be true, and therefore offer a level of confidence in their claims. When dealing with an international producer, I have less confidence in the truth of their claims.
While I haven't sewn with the fabric a lot, I love bamboo fabrics, especially the jersey. They are soft, drapey, and can be luscious on the skin. Yes, its likely they won't last years and years, and the price point will often reflect the nature of the growing and production methods (small scale), but if you can find a good source of fabric, its worth it to support smaller producers.