Free weights are a great way to achieve an all over workout. The difference between a free weights workout and a multi-gym work out is that with a multi-gym you are restricted by having to repeat the same motion on each muscle group, but with free weights there are several different exercises for each muscle group. Using a variety of different exercises on the same muscle will increase its efficiency casuing it to perform better and give a more toned apperence. You can also isolate specific muscles which require toning or increasing in bulk. Free weights are also a great way to get a rewarding work out with limited space.