Honestly I use either what I have on hand or what needs to be used up. I'm sure there are purist who suggest using all natural, blah blah blah....but any protein free should be useful. Now, if you have to purchase conditioner in order to make gloss, that's when you should get what you prefer.
I use whatever I have on hand @Daina. Cones and all. It really doesn't matter. Giovanni Direct is an awesome option by the way. I use deep moisturizing conditioners and cheapie conditioners like v05 with great results.
@mzteaze, @Aggie thank you both! Just wanted to make sure it wasn't because there wouldn't be some weird reaction using cones. I am quite okay with cones and they work well with my hair. Wen is my preference, but Giovanni is cheap and I can get it on the ground.