There's nothing wrong with machines, except being less effective than free weights. They're still solid though, I got in the best shape of my life one time only on weights because I worked really really hard at it. But I accomplish 80% now with 40% of the time with free weights and compound exercises.
One of the big criticisms Rippetoe makes of machines in the book Starting Strength mentioned in the article is that because they can cause unbalanced muscle development and increase the chances of injury over the long run.
I do something similar. Two days/week: heavy weights, primarily machines (+cardio). Two days/week: free weights, compound+core exercises. Much lighter weights- still a grueling work out.
