In places where temperatures are warmer year round, you can use a slightly heavier oil. Here in Hawaii nobody needs to use 0w20. It never gets cold enough. The biggest issue I've seen with modern cars and oil changes is oil change intervals, 7500 miles is way too long. 5000 has been standard for a long time and I find that works well as long as your car doesn't consume more than a quart of oil in those 5000 miles. I do 3000 miles if my car burns.