From what I gather the formulas only vary slightly from another to better provide for the specifics but could be feed across the board with no problems.
My Old set up had... Tropheus, Petrchromis, roselines, Cyathophranx, MBU, bristlenose and I fed the tank mainly 1mm cichlid formula and maybe 1lb of Thera+A mixed into the 5lb bucket. Worked out great! (MBU ate larger pellets only unless I pinched some smaller between my fingers and waited for him to snap).
I think a sole diet of Thera+A is not ideal for the humans... the water gets a strong odor of the garlic and the water does cloud a bit from overfeeding that stuff. I can over feed any other formula but Thera+A gets pretty nasty at times.