I would like to switch feed for 2 horses that have recently arrived at my barn. They are currently on Equine Senior (the horse is only 10) and Legends sweet (11%). I would like to switch them to a decent quality pellet feed & I am looking for something with no more than 12% protein, around 15% fiber, about 6% fat, and no more than 1500 calories/pound. I am looking to spend no more than about $12/bag. Fortunately, I have access to quite a variety brands, some of which are, Southern States, Purina, Blue Seal, Triple Crown, and Nutrena. Thank you...all information is helpful...even if you can tell me what NOT to feed.