Congrats on your flask purchase!
Any of the methods you have read about will work. I'm partial to compotting paphs right out of flask into either a single pot or two pots. I hate to disturb plants right out of flask too much. I have been using the "with agar" method lately with good results. I have taken the mass of plants out of flask and put them directly in a compot. In the compot, I've used 100% sphag with good results. I'm now trying a fine Aliflor (sp?) mix with cocoanut husks and charcoal with a sphag top dressing that I keep moist until the seedlings get going and show new growth.
I visited a fellow grower over the weekend that does his own flasking. He is now using the clear plastic folding "clam shell" containers to compot in right out of flask. He gets these containers at his local grocery store. They package ready-to-eat salads in them. He burns drainage holes in the bottom with a soldering iron, puts the seedlings in with sphag or other fine mix, then puts them under lights until they are ready to pot individually. He is having excellent results. He keeps the seedlings moist and fertilizes lightly. I am now sold on his method.
I do not have experience with s/h on paph seedlings right out of flask. Young plants out of flask have small and tender roots. I believe I would try to grow them up before I transferred them to s/h.
Just remember, handle the plantlets carefully. Minimize handling overall. Whatever method you use for compotting, DON'T LET THE ROOTS DRY OUT! Young seedlings can't take this!
Just to make things a bit easier, next time consider having the grower sending you the plants deflasked. Breaking flasks is no fun and deflasked plants ship cheaper.
Also, your flask style doesn't look too user-friendly. I would consider carefully breaking this one because trying to fish the plants out through the side-spout with a long set of tweezers may result in plant/root damage. You want to avoid as much shock to the seedlings as possible.
Hope this helps!