I always give them timothy but I'll add an additional handful of something else(oat, meadow, alfalfa, botanical, etc...). The alfalfa is rarely give though.
All my boys get Timothy Hay as their staple, and then meadow and herbal hays as a treat. Twice weekly they all get a small amount of Readi Grass as a special treat. Yum Yum!!
My girls get Oxbow Western Timothy.... though I did try offering them Oxbow's Oat Hay at one point. They weren't so into the oat hay, so just the timothy for them