Dont listen to the nay-sayers....
I run "all" skinks...not a Saurus in my army.
I have 3 block units of Skrox, one with 50ish Skinks and 4 Krox. Immune to fear, immune to stomp, steadfast virtually to the last man.
48 Skinks/4 Krox
24 Skinks/3 Krox
24 Skinks/3 Krox
25 Skinks
2x 15 Skink Skirmishers
10 Cameleons
Something key to remember about the Skrox unit...the Kroxigor count as the number of Skinks that they displace. This means that 3 Krox count as basically 2 full ranks of Skinks. Remember that when counting combat res, but especially for counting Steadfast.
This is a little twisty in the new rules and I expect this to be changed in the new book, but for now this works great.