I've had LTD for about 20 years, since my first DD was born when I was in my 20's. My employer at the time offered a so-so policy at a single premium for all employees. Being young and healthy, I found that I was eligible for a much lower, age-based rate through a professional society's group plan.
I later had a high-end STD / LTD policy fully paid by employer #2 - 100% of salary for 90 days, then 60% until age 65. Disability was defined as unable to do the job I had at the company, not "any" job.
Last year I went to employer #3, who provides at no cost an LTD policy with 50% salary coverage from months 6-24. (I guess with that span of coverage there's a lousy assumption that those eligible to make a claim on the employer's plan will qualify for Social Security disability before their LTD benefits run out...)
For an out-of-pocket payroll deduction, they also offer a flat-rate supplemental policy that raises the coverage to a more traditional 60% of salary from 3 months through age 65.
The math in comparing the company supplemental policy's premium to a policy I could get on my own worked the other way for me this time around, at age 47. I compared the professional society's age-based premiums to the flat rate for the supplemental policy at the job. This time, the premiums were about even for the next couple of years. After that, however, the age-rated premiums started jumping up significantly.
I went with the employer's supplemental policy. Right now, I plan to keep it in force until I ER or DD#2 graduates from college, whichever comes first.
No claims stories to share, knock on wood.