I've been researching used GX 460/470's trying to determine which vehicle best suits my needs. I will be towing a lightweight T@b camper and I live in Colorado, so I will be traveling over high altitude passes. I currently drive a 2017 BMW X3 which pulls the camper okay, but I worry about the wear and tear on the BMW. I've owned a 2004 RX330 and loved it, but I need a vehicle with more off-road capability and power. I'm looking to stay around $20K in price and I think I can find that. I just don't know the differences between the 460 and 470 (other than engine size, obviously) and the differences between generation 1 and 2. Pro's and cons?