Bro,
I wouldn't use that routine if I was you, unless your just simply trying to break some form of monotony.
Now lets clear up some misconceptions...
Low reps and Heavy weight don't neccesarily = growth! Thats a ridiculous misconception. Most models/bodybuilders dont even train heavy and if they do it's usually only periodically.
As most people find out, those who have the "go heavy or go home" approach will usually not be using the same approach by the time thier in thier late 30's..the body will eventually get tired.
Now with saying that, I will say just to illustrate my point look at alot of power lifters/olympic lifters physique. I'm not talking about the big fat "heavy weights"...im talking about the guys who have to "make weight" to compete. Usually these guys look more in line with "Mens Health" models then they do with bodybuilders and guess what....they usually train heavy and frequently!
Look at the likes of John Inzer..around a buck sixty-five and deadlifting close to 700 lbs! Or maybe to look at the old timers before AAS even came upon the scene...Arthur Saxon could one arm Bent press over 300 lbs..he weighed approximately 170 lbs..Sigmund Klein maybe 190..all thes guys were phenomenal strength athletes!
Again training heavy
does not neccesarily = muscle hypertrophy...more often than not you are training your nervous system more when you go low reps and heavy weight.
Now I know your going, "So what what does this mean to me?" Well what is simply means is it's alright to work-out in the 3 sets of 8-15 rep range and you'll probably get some new growth as well as maintain what you have better then if you had gone heavy.
As for circuit training....it sucks as "Citruscide" said, it's more of a marketing ploy then a effective means of working out unless of course your apart of the 90% of the herd in our fat, lazy,overweight society. Beleive it or not reducing the the rest in betweeen sets can be more dangerous then lifting heavy for low reps

When you dont have suffecient rest(even with ken and barbie pink dumbbells) you set yourself up for an injury by tiring out your stablizer muscles and youeventual failing to perform reps in excellent form.
I want to make clear that I beleive that bodybuilding is as much ART as it is science so that means different strokes for different folks...but I wanted to also make clear that heavy weights and low reps do not neccesarily = muscle growth...
Hope this helps
TH
