There is a lot of good info in this thread. BurbMan and JBarca have excellent suggestions, in fact John's could be a sticky.
The details about "How To" get this right are here, the real issue is what you will talk yourself into based on other variables. Don't take this personally, we all do it to some extent or another.
The classic is someone that has a half ton, does not want to buy a new truck, then tows or hauls something that is too heavy. They then talk themselves into believing that it is OK because others do it or because they did not crash on that first trip.
This is hypothetical, I'm not putting words in your mouth, but lets say your DW was pressuring you to get the 1/2 ton, and or one of the imports because she likes those trucks for her needs. You could feel pressured to make that vehicle OK for towing and talk yourself into it when you shouldn't.
Like I said I think many of us do this to some extent or another. You are in a GREAT position in that you can start fresh and buy the exact right thing.
