When they say that it doesn't give as good of a work out they mean that about how you don't have to balance the weights like when using dumbells, and doing a bench. Which in turn does work smaller muscles not normally reached when in a controlled atmosphere (Any machine that has preset/moderated path the weight/resistance travels on). And on top of that during certain excercises such as leg extensions, curls, and some others you can't get a full extension/curl with the stock length of the cable. By limiting the amount of movement (due to the cable) you limit the amount that the muscle can be worked.
I know you can do more reps of a lighter weight, and less reps of a heavier weight depending on if your more interested in toning, or building mass. But I personally have seen better results on myself due to free weights. I've personally spent close to 2 years using a bow flex, and then I switched back to free weights due to similiar little factslike those, and I've noticed that when I went back, I wasn't used to balancing the weights as well as I used to be, and I fatigued more quickly while using free weights.
I'm not sure if other people have noticed anything similiar, but that's my personal experience. For the simple fact that it's a comparatively small machine (compared to all the equipment you'd need to do all the similiar work outs) I do like it for certain applications. Such as not being able to get to a gym due to various reasons, but if you have the means and access to a full gym, I'd say take advatage of that.
~Bill
p.s. I Hated how you had to reach beneath your bodies full drop to get under the bar for squats, I don't know if they changed it, but you had to take some of the weight in your arms, then get under the bar with weight on your shoulders at all times, even while fully compressed at the Very bottom of the lift.