Hear is a great resource for educating yourself of buying a used truck.
http://www.amghummer.com/features/bu...uyingUsed.html
I never used it as I have wanted one since 92 and waited/learned for 10 years before I got one.
Comfort level is all relative. When I was growing up I was always in a sedan. My parents always had a cadillac and for me it was really uncomfortable. I will always choose my truck over any other vehicle. Although driving our company International 20ft long stake body can be fun at times
Doing your own maintenance is really not that big of a deal. Some of the more complicated stuff I let the dealer handle but regular fluid maintenance/inspections is rather easy and fun but can be time consuming.
Pick up the maintenance CD at
http://www.bluehummer.com as well as the Factory maintenance manual. It really helps you out and explains everything really well. Also people are your best resources. Someone has always had an issue that is willing to help you through the situation.
I starting learning a lot of it way before I even bought a truck. I have also never changed oil or serviced another vehicle before my truck so you are a head of me.
Where are you from.