My Julep "Nail Therapy" lasted from my first Julep Maven box, months ago, and came with me all the way into this holiday season. This is an amazing product.
You can use it, as the website suggests, either as a separate "therapy" treatment or as a basecoat. It dries really quickly -- I would often toss on a coat of this before I headed out for the day, and then actually polish my nails over it that night. I also could always tell if there was a nail that missed its Nail Therapy basecoat, because polish would not adhere as well, and the nails often would be weaker.
This is also a great choice to solidify a small tear in the nail. In some ways it seems more solid than even a mere nail polish, but it is super thin and does not overly build up a manicure.
My only comment to frequent users of this product is that you should be very careful to seal your bottles carefully between uses to preserve hydration. Near the end of my bottle it got it a little bit gummy, probably because I am the worst at sealing my polish/treatment bottles.
I loved using this product underneath all of my manicures, and I am grateful to my little bottle for months of great work! Hopefully I will be able to pick up another one soon -- this is the best product I have found as a basecoat, especially for my Maven reviews. :)