I just came across their website http://gristandtoll.com. Are they well known to TFLers? I'm a newbie, so I wouldn't know. Their varieties sounded enticing.
I have and do pickup their flour. Well crafted and recommended.
I should also mention that you have a great resource "The Los Angeles Bread Bakers" group on meetup.
They have classes and other meetings that can really cut the learning curve of all things Bread..
I'm a customer, too. The store front is new since last fall, but easy to find. I was lucky enough to meet Nan, the owner, who kindly helped me select flours that suit my needs. I bought several flours and have enjoyed working with each of them. Open the bag and take in the aroma... now imagine how your bread will taste!
You might like to check out THIS site where MC, a long time member here, just wrote an excellent review about her recent visit to the mill. Very impressive undertaking and, in my opinion, one that hopefully catches on in other cities.
If you are going to be in Pasadena, you should drop by. When else will you get a chance to meet your miller? I went a month ago and even the non-bakers in my group had a great experience there.
Just a quick pic of G&T ww (left) compared to Bob's Red Mill ww (right).