I have read some posts on these 2 workout systems and want opinions on which to buy? I would love to buy cathes sts series but its a bit pricey for me and these are cheaper and from what I have read , people are getting good results from both of these. I want to increase my cardio endurance for my races and I want to lose about 5-7pds also. I want to become leaner and more fit overall. I want to add something new to myworkouts to help me get over this platuea I am at. I currently run 4 days a week and teach a intense bootcamp class 1-2x week. I have been able to maintain myweight but not lose any since turning the BIG 40! I think I will eventually buy both of these series but want to start off with one and then before my cruise in may get the other series to change things up again. so which to buy first? thanks