If it creates a calories deficit for you it is good for cutting. The 300 workout is a "conditioning" method. It is good for fighters, wrestlers, etc. It can burn a lot of calories but it can also be very difficult to stick to. It leaves you exhausted each and every workout. Some like that sort of thing, otehrs don't. You will also need to have certain types of equipment available to you and a gym that caters to that sort of training.