Yes it is good training. It addresses nearly all aspects of fitness, increasing flexibility, strength, and endurance. I have been at it for 3 months now and have become noticeably stronger and faster. You don't use machines, you learn to use you body. You do Push-ups, sit-ups, pull-ups, muscle-ups, etc. You will also use a barbell for basic weightlifting. It's great.
It is very intense though, so it will test your drive and determination, you just have to grind through it. Once you finish though, you will feel great, there is nothing like it.
Everyday is a different workout so it is always changing, so you won't get bored. Definitely worth a shot, and most CrossFit gyms give free workouts to let you try it out for awhile.
CrossFit offical website if you're interested in some of the workouts and are looking for more information.
If you try it out let me know what you think.