This site is amazing. I had a real problem with nerves during interviews, I did about half a dozen practice interviews on the site over about 2 or 3 months, while I was brushing up on algorithms and data structures in my spare time. It was great, if you have issues with interviews I recommend the site.
One bit of advice though, don't just jump into a mock, make sure you prep by studying first for a few weeks.
One bit of advice though, don't just jump into a mock, make sure you prep by studying first for a few weeks.