We have flown into Ontario twice, it saved us a ton of money. Its a nice airport, the quickest security we have ever had, it didn't seem all that crowded. I think it might be used mostly for Fed Ex and the like. We are lucky, my fil picks us up since he lives nearby so I can't comment on shuttles/rental cars. But the last time we landed there it was around 6:00 p.m. and I was bracing for bumper to bumper traffic. Luckily it went really quickly, the traffic seemed to all be going the other way. I think it took just about a half hour to get to the Paradise Pier Hotel. Same deal when we flew out on an early morning flight returning home, manageable traffic, moving right along for us, but much slower going the other direction.