I did uberman in grad school, kept it up for a few months. It technically did give me more hours in the day, however most of that free time was spent on either making sure my schedule was arranged well enough for my sleep times, or sitting around reading a book quietly at 3am because everyone else including my roommate is asleep and all businesses are closed.
The benefits weren't really as pronounced as I was hoping for. Then if you end up missing one of your scheduled sleep times it really effects you and throws you off for a day or two.
I did biphasic for awhile and had a lot of the same issues. I DID get more hours, and I enjoyed doing it, but my family did not. It was impossible for me to do a full time job + family time + biphasic, and have the least bit of wiggle room for a dinner out, or a movie, or anything that took longer than planned.
The benefits weren't really as pronounced as I was hoping for. Then if you end up missing one of your scheduled sleep times it really effects you and throws you off for a day or two.