US Steppe cammo ?

A question to our US military experts:

This came up in another mailing list.

Assume a fight in some country that is mostly
steppe/prairie/pampa/savanna/open grassland. What would the vehicle
camouflage pattern for US vehicles be ? 

Among the older MERDC paterns, I would guess it's the 'Summer Verdant'
(see
e.g.http://www.burleehost.net/ontheway/articles/MERDECcamouflage.htm).
Is this still valid ? Or are there new patterns after the introduction
of the NATO patterns ? 

Any experience from exercises in such an environment ?

Greetings