I've heard great things about 531, personally I have not tried it but the principles are sound and the anecdotal evidence speaks volumes about it.
I've tried the prepratory base cycle of sheiko (4 a week) and got really great strength gains. However, I believe you should really pair it up with some kind of peaking cycle (I believe sheiko has one setup). The base cycle has you handling relatively low intensities at really high volumes, so when the weight goes up you're just not adjusted to it. Thats my only qualms with sheiko.
I'm currently doing 5-3-1: it's a very good program, as long as you can figure out what assistance lifts (and at what volume and intensity) suit you best. Others programs are more strict (Starr/Madcow 5x5), which can be useful if you're not shure on how to set up your assistance lifts.
There is no "best" program. There might possibly be a "best program FOR YOU" but that is a pointless argument. Any of the programs you listed have sound principles and plenty of real-world success stories behind them. Pick one.
Once again this all gets down to what you want to accomplish. You have to look at your goals and see what you're trying to do and what training program will get you there. Above all, it has to be something you enjoy doing, or else you will not do it or only do it half assed. This is my little cheat sheet of the different programs:
If you have a lot of time to train and ability to recover: Sheiko
If you want to powerlift competitively: Westside
If you want to be "cock strong": Wendler's 5/3/1 (a direct quote from him)
If you want to be strong and be a bodybuilder: DC
Any of these can be done for 3 or 4 days a week, with the possible exception or Sheiko. This is just my opinion, so take it for what it's worth. If you choose a program tho, stick with it and don't try to bastardize it or mesh two or three together. Programs are written the way they are and work for a reason.
^^This is the best piece of advice that is never followed.
Sheiko is good if you tolerate volume, and your goal is purely PL'ing. You will get good at doing the lifts, they will become automatic. But as said before, you need to pair it with a peaking cycle, and most people are doing well with two 4 week training cycles followed by one peaking cycle (12 weeks total). Sheiko is good if you want it all laid out for you and you don't want to think at first. (it can be done 4 days/week but only recommended for the advanced lifter i.e. CMS/MS, or 5 days/week for the highly advanced MSIC) Once you've run it a few times, you can start to tweak it.
Westside is great if you are good at identifying your weaknesses and like to move heavier weights. If you are motivated by breaking PR's on a weekly basis, then you will like this style. Westside is a template, and you need to be able to plug in your own exercises, and honestly identify what needs work, and which supp/assist movements are beneficial to you.
It seems like a lot of people are doing 5/3/1 and liking it. I don't have any experience with it, but if Jim says it's good, then it's probably worth trying.
I'm in the middle of the pendlay 5x5 (start the deload thursday) and I'll be switching to ws4sb when it's over with one twist. I read once that Defranco said it would work perfectly well to go 5/3/1 and then deload and then switch exercises within the ws4sb. I'll be doing that for 4 months as I play volleyball all summer.
I think it really depends on what your goals are and how you like to train. I train for competing in powerlifting in unlimited gear, so I structure much of my training around that goal. Some stuff- like my accessory work, back training, etc.- might be the same if I were training for raw competition, strongman, just being strong, etc.
Also, the longer you do this stuff, the more you will find that any program is really just a starting point that requires a lot of tinkering to make it really work for you. For example, the "Coan-Phillipi" deadlift plan is a training plan that has circulated on the internet for years built around an undulating peaking plan for deadlifts, speed pulls, and upper back and other DL accessory work done in the same workout as the deadlifting. Personally, I found the peaking plan did not work well for me. I pulled sub-par weights for doubles every week, so I became better adapted to pulling sub par weights for doubles. This did not translate into the ability to suit up and rip a big single. I also do better doing my upperback work on another day. But, I liked the speed triples the program calls for. These improved my bar speed off the floor. So my deadlift training going forward has gone to pulling singles up to a max or near-max followed light triples for speed with most accessory work happening on a another day. This is just an example of what I do to make it work for me. Your mileage may vary.
At the end of the day, the plan should complement your goals and needs- not the author's.