Well, I've decided to try Flexinail after reading through quite a few topics on nail issues on this forum and elsewhere and studying the pros and cons of various remedies. Even on the online seller of everything, there were classical guitarists who commented positively about it. I had previously tried Alaska Piks as well as "Hard as Hoof" nail strengthening cream. I did have some modest improvement with Hard as Hoof and it's cheap to buy so I might still use that at bedtime, although I'm not sure if combining these things is helpful or not.
I started using the Flexinail a couple days ago. I will try to give it a good 6 months or so and see what happens. Fortunately I have a job where I can apply it and leave it on for 20-30 minutes and do that 2-3 times a day.
If anyone has any additional special tips on using Flexinail, that would be great.
This stuff is not cheap, that's for sure, so I really hope it works and if it does it will be well worth it to me!