I dont have the rules for SM Scout snipers but id love to add a unit of these guys as allies instead of ratling snipers, im just not a fan of them.

I guess this question would be two pronged. Could I use scout snipers instead of ratlings or would the wysiwg rule prevent that.

The other is is it worth having them instead of ratlings, is there any drawbacks?

I appreciate the help guys thank you.

whether you could count them as ratlings is going to be a bit split.

I personally wouldn't care. Alot of people wouldn't so long as you let them know what's going on.

There's a good deal of people out there that would feel you can't do this becasue the fact that they are ratlings is what WYSIWYGs their go to ground rule.

finally the offical tournament ruling, absolutely not. for the counts as rule you have to have a model to represent it that is A. not confusing to your opponent and B. It can't be from the same system. which basically means it's OK to call an Empire gunman an imperial guardsman, but you can't have a sister of battle as a space marine, or a kroot for a dark eldar.

Well first the only way to include them into your army is to take a second detachment. This is normally only open to players when playing games of more than 2000-2500 points. So unless you are playing large games you cannot mix Space Marines with your IG. That said, if you do play a large game and use a second marine detachment, then you must use an HQ and two troops(Snipers are troops in some Space Marine codices, elites in others)

As to using them as Ratlings I would say no. The Count As rule, is used for such things as using non normal units as something in the codex. Simply using Space marine scouts as something else is a no no IMO. Especially since that would be confusing to players. If your group agrees go for it though.

Also remember(Although I say this just to remind you)Apocalypse is always an option.