Which mix to pick (first time bark user)?

[Pumpkin92]

So I don't know how or why I caved, but I just came home with three new phals... The problem is two of them are in 4 inch pots and that's way bigger than anything I've had to deal with yet. They aren't in clear pots so I can't see how good or bad most of the roots are but I'm thinking its time for me to try a bark mix.

The only options I have in my area are:
Gubler Organic Orchid Mix FINE grade
Gubler Organic Orchid Mix COARSE grade
BETTER-GRO Organic Orchid Mix

(Btw, I'm still gonna mix sphagnum moss in there because my home is really dry and I don't think I could do straight up bark.)

So does anyone have experience with the above mixes? And any suggestions for a first time bark user?