Not something I normally do but:
Out of all them the Lanard figures have the best articulation with swivel arms, elbow twist and bend, waist swivel, and t-legs with knew bend. The Kong Skull Island figures are repainted Lenard The Corps figures with custom mold heads that - to various degrees - resemble the actor. In fact Sam Jackson and the Corps figure next to him share the same body. The biggest problem with the Corps are the "fodder" toys. These are the Corps and Kong skull island who can only move their arms are the shoulder and the legs at the waist. They look cool and are well sculpted but as a toy ... they don't work as more than a quick death or setting decoration.
The problem here is in the heads. The typical Corps figure has a slightly larger than average head lending to the action cartoon style of the figures. With the Sam Jackson head being more proportional to a human head it gives the illusion that the Kong Skull Island toys are slightly smaller.
The True Heroes toys are more closely designed to classic 6" action figures like first run Toy Biz Marvel/DC superheroes, or Kenner's old Super Friends. They have basic up and down arms, elbow bend, t-legs and bending knees. Outside of that they're paint jobs aren't as well defined as the Corps figures, but are slightly more sturdy ... they feel heavier. Were True Heroes comes through is in the vehicles which aren't pictured here. They're better built, larger, and have a lot more variety than the Lanard. My suggestion - and what I have been doing for my son - is to buy Corps figures and True Heroes vehicles. Outside of the above the biggest disappointment with the True Heroes is the price. Two figures for around $7.00 is pretty good, but Lanard's the Corps give you 3 figures for the same price and feature the better articulation, etc.
Finally the "Army of One" figures and/or their Navy "Seal Team" reprints are a collection of the worst aspects of both the Lanard "fodder" figures and the True Heroes figures. The "Army of One" figures are pre arranged and you can usually move either just the arms or just the legs. The ball joint elbows or hinge elbows of The Corps and the True Heroes is missing here, making the characters very, very limited in what you can do for them. My son usually uses these guys as "the fallen" when he plays. Further the painting is horrible on the figures, if you look closely you can see the makers flesh-tone painted over a beard that should have been there with no regard, and spots of overly thick paint or too little paint can be seen all over the toy. The sad thing is that these guys cost a prime amount, almost as much as a GI Joe two-pack but features none of the reason or fun as to why to buy.
Lanard's Corps and Kong figures are exclusives to Wal-Mart in the United States (and I think K-Mart in Canada). While True Heroes is the house brand of Toys r' Us (get "TRU" Heroes). Army of One I have only found on amazon and at super markets so take that as you will.