I've played probably the first 5-6 scenarios with the pitslave v3 rules now and a good few with the v2 also. Here's my thoughts so far.
Positive feedback regarding v3:
Servitor got better and I think it's now very flavorful and overall pretty balanced (there are however a few issues mentioned later).
The techno got one more in BS, which is nice. He's still not a warrior per say but now he can do stuff aside from flaming and buffing the servitor on the field.
Issues:
The servitor rolls for XP on purchase. All XP gained this way can do is add to my gangrating. I suggest setting it's XP slightly higher instead as the roll seems pointless.
The Pit Slave Chief has the "many arms" rule, but no other pit slave can get a third arm in any way. Therefore, if your leader dies, there is no way you can use that model again, if it has a third arm with the gang remaining WYSIWYG.
The Servitors roll on the programming table may mean that you may pick a skill from the shooting skillset for it to have during the scenario. Problem is only crackshot does anything with heavy weapons, which the Servitor will nearly always have. Were the skills ment to apply to heavy weapons anyway?
A one armed pit slave with a knife is the cheapest fighter you can possibly acquire. He costs 60 credits. Pit slaves have to do very well in a scenario to earn 60 credits, especially if a few are out of action after it. This means although your gang starts out at a pretty usual 8-10 slaves, after a few games you might well be at 6-7 and without the 90+ credits it takes to buy a fully equipped pit slave.
General observations:
The servitor feels pretty dull due to it not gaining experience, although it is pretty effective under the new rules. A way to upgrade them other than experience might be a good idea.
As a fix for the many arms rule, maybe making the "many arms" rule a gainable skill for pit slaves on a 2 or 12 on advancement if the pit slave has 81 XP or above?