I don't have any real experience to answer most of your questions, but on the fuel line I've been switching my stuff to the Aeroquip AQP Socketless hose ( what is also called Push-Lok ) over the past 15 years on the initial recommendation of a friend, no issues and I really like it. I do generally run race gas in the race car, but I did run ethanol infused pump gas while on Dragweek a couple years ago and I switched the hoses on my '78 Lincoln before dragweek last year. I have it on a couple of my other old cars too. Seems to hold up well. Some of my friends have been using the Aeroquip Startlite hose to plumb their race cars recently, haven't heard any issues. I personally stick to the Aeroquip brand stuff, I haven't tried the Summit, etc. copies. Initially some of the copies were not NHRA approved, but I see lately most show approval.