Orchid Pots for Phals

[labyrinth1959]

I want to get some new pots for repotting my phals. I'm leaning toward the clear plastic pots because I would like to be able to see the root growth. I have some questions for the experienced growers. Would you suggest slotted pots; pots with only vent holes in the bottom; would you drill a lot of holes in the sides? I notice that there is pot available that looks particularly interesting called a dual oxygen core pot. Thoughts and suggestions are appreciated. Thanks!