x4 or so for Pilot/Flying J as long as you can afford the price they charge for their fuel. Before the merger I travel FJ to FJ. Now, I go to PFJ only if there is no other reasonable choice. Yes, it's easy but you can often find easy at other stations as well. All you need to fuel at a P/FJ is their RV card. You swipe it at the pump, fuel and then go inside to pay. It's a better option then using the P/FJ CC or account as your CC likely gives you better cash back rewards than the discount their card offers.
In any case, if you do choose to use the truck lanes in your RV you don't need to make any special considerations for the truckers. You are just the same as they, we both need fuel. Get in line, pump 'til it's full, pull forward after pumping if you need to go inside and then pay and get out of the way.