Saurus warriors are considerably cheaper than Temple Guard (12 pts vs 17 pts) and they do not have to be fielded with a Slann Mage Priest.
You might want to consider giving one Saurus unit a Sacred (sometimes called Blessed) Spawning to further boost their abilities. Note that taking a spawning will turn the unit into a special unit choice (taking 2 will make it a rare unit choice so don't do this !)
You can afford to give one unit a sacred spawning if you choose not to take Saurus Cold One Riders Cavalry.
If you're fighting Wood Elves or over a battlefield with a lot of wooded terrain you definitely need the blessed spawning of Huanchi to negate movement penalties.
Otherwise your favoured and exceptionally cheap choice (30 pts) should be the blessed spawning of Sotek which provides +1 attack on charging. A unit with this spawning should be deployed as a support unit to engage enemies already tied up in combat - this is to make sure you get to charge and use the charge bonus as many times as possible. Place this unit next to your Temple Guard which will usually be the main core unit for taking the fight to the enemy (note: you don't have to do so when fighting Dwarfs because you should always be charging 1st anyway)
Saurus will hold their own in fights against nearly all rank and file opposition. They are your key to victory so you should take several units of 15 or 20 including standards and musicians in a 2000 pt game (I'd recommend 3 units of 15 plus a larger Temple Guard unit)
Saurus can be given spears for +2 pts each, don't bother with these because you will usually be the army on the attack. Take them however if you're facing Bretonnians or you expect Empire knights or any other fast moving opposition which are likely to charge 1st.
Happy hunting my lizard friends.
