Yes they seem like very good people, they've always been very helpful. I have never used Barge but have used several other contact cements and they are pretty much the same , 20 or 30 minutes usually is ok. You do need to scuff the smooth surfaces quite a bit for good results, sometimes a second coating is helpful.
Some people like olive oil instead of nfo. I don't think you need extra virgin, just the cheap stuff, but I'm not an expert on any of it, just my experience.