I use gold plated when ever I can, that said after many years of breakdowns on mine sites i can say that 90% of electrical dramas will be the wire itself not the contact between pins. Non tinned wire is terrible. Assembly is key, people not putting the blanking plugs in is a killer. also corrosion x sold by snapon over here is the awesome, a little squirt of that keeps moisture out and the seals in good cond. I dont rate dialectric grease.
So after all that, if your wire is good quality then non plated pins when nothing else is available should be fine.