In general, when flying a turbojet/turbofan airplane, one should be fully configured and stabilized no later than one mile inside the outer marker, assuming IMC. Early in my jet flying career, I would cheat a little, mainly because my department head wouldn't set any standards (he didn't want to paint himself into any corners

). Once I hired on with a good outfit, and was trained properly, I saw the light pertaining to stabilized approaches. Having had the peedoodle scared out of me in my earlier job made it easy to come to this conclusion.
But here is my basic reasoning for stabilized approaches.
First is because stabilized approaches are uniform, i.e., the next one is the same as the last one. It is much easier to recognize error, when you always do the same thing at the same time. Second, a stabilized approach is the best way to recognize windshear. Even when your bird is WAGS equiped, stability is important. Third, it's a heck of alot easier to fly precise approaches when you aren't trying to change speed and/or configuration inside the FAF. Fourth, having the airplane set up frees your mind to concentrate on other more important things, such as what are we going to eat on the layover.
Additionally, If you ever get asked to keep your speed up, don't try and stay clean, go ahead and get dirty. You will burn a little more kerosine, but it's much easier to slow from 180 to 140 by just pulling power than it is to slow by adding drag. Unless your bird has low flap speeds that is; the old Maddog has me spoiled in that compartment and going 180 with landing flaps is no problem.
Non-stabilized approaches are just too much work.

Like I said, I'm just lazy.
regards,
enigma