A/C question

[NOSed69]

I am starting on a new project truck and have a couple things still up in the air. I am using an air cab 72 that has had the a/c evaporator open for a LONG time. Whats everyones opinion of the POA valve?? I have no expeiernce with them and dont know how they operate? I see in searching here the Oldairproducts.com has POA conversions, but they also offer a new evaporator that accepts an orifice tube?? Since I'm building a system from scratch only starting with the original evaporator( assuming it pressure checks ok) What parts should I use? BTW, work in auto/heavy truck parts, so sourcing pieces isnt a problem. Just not sure what parts will work the best together!