I just went out and picked up all the pieces for this MLT. Went Stainless and took the advice from Schnitzengiggle and went with the 3/4" Water Heater Supply braid with the 1/2" stainless compression spring. Bargain Fittings had great prices on pretty much everything. Glad to pick up the materials (minus cooler, supply brain and compression spring) from a site sponsor.
Also picked up a step bit and 3 piece stainless steel ball valve for my kettle. Moving on from BIAB to help with the bigger beers.
Cheers for posting all the helpful info!