I've used ACT's, I was just wondering if I should learn Craft Packet systems which I've only ever used once to make some Diamond Shards for the Wrath Igniter.Easiest would definitely be using filters to pull things out into your tubes and into chests attached to Automatic Crafting Tables from Buildcraft. The ACT will use items from attached inventories. I don't think you can use a filter to pull things out of the ACT, so you'll have to go with a BC pipe + gate/redstone engine pumping to a relay to get the items back into your RP system.
Wait until fabricators come in Xycraft, they look real sexy.......
Go look at S04E25 of Direwolf20's youtube series......