Now that I'm done with 5/3/1, my thoughts:
It's a great program, but I'll be honest in that I wouldn't think so without having made the adjustments to it that I did after the first cycle of 4 weeks, which constitutes half of my stay on it. In the 8 weeks that I was on it I couldn't get around how <i>light</i> it has you going. You're supposed to calculate your numbers using only 90% of your max. I didn't freak out about this or anything like Wendler predicted some might, but it became apparent that this was the element holding it back for me.
On a day that has you doing 3 sets of 3, for example, you're actually allowed to take your final, heaviest set and do as many reps as possible. It's listed as 3+ to indicate this. Well, what's the point in even mentioning the 3 or calling it a 5/<b>3</b>/1 if I never get anywhere near 3 reps? Usually it's something like 11 reps. I wouldn't have any problem with that (high rep deadlifts were the breakthrough I needed to get my form down) but that's throughout the <i>entire program</i>. If my bench max is 335 I'm lifting 286 lbs on my heaviest day of the entire 4 weeks. That 286 is supposed to be for 1+ rep. I'd end up hitting that for 8. And remember, that's the heaviest week. Everything else is even higher. I'm rarely ever lifting anything less than 10 reps by sticking with 90% and then doing 65%-95% of that 90%.
Wendler goes out of his way to insult meatlings who tinker with it (which is awesome) but even he acknowledges what I said by way of his new version "5/3/1 for Powerlifting".
In my opinion, it's very viable for novices to intermediates who still need to get the grooves down but I had better success ignoring the 90% limit and doing lower reps in all but the first of the weeks.
At the start of doing it, my stats were:
Overhead press: 175 x 5
Bench press: 305 x 2
Squat: 375 x 3
After 8 weeks:
Overhead press: 205 x 2
Bench press: 335
Squat: 415 (deeper, as well)