When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Something else to consider is are there any diesel mechanics in your area? It is something I have to consider as I research getting my first diesel truck. In my small town, the only place I can get a diesel worked on is the local Ford dealership. Getting your truck worked on at a dealership tends to cost you more than independent shops... at least around here. If you have any friends with diesels I'd ask them about where they get their engines worked on. Just food for thought.
I would go with the V10. Seems like it is probably more reliable. If you don't drive too far in the week, then you shouldn't have to worry too much about gas. Besides, gas is a bit cheaper than diesel.
As someone already said you have to decide. I would love a diesel, can't justify it. I also would never have been able to find the truck I currently own or any other crew cab truck with a diesel for the price I paid for it and with the mileage (under 26k!). I don't care what motor it has in it, 100k+ miles wears on other parts that if they havent been fixed will definitely be fixed on your dime. When I was a kid my dad always said that to me when I wanted to buy and older truck. "Better have deep pockets for all those needed repairs!" I'm not saying a 100k truck's doors will fall off but wearable parts well...wear out. My previous truck was an 06 250 and I picked that up with 27k and by 38 or so it needed new brakes and rear calipers(my dime), new bed (Ford's dime), and other nickle and dime stuff that the previous owner didnt care to take care of. I live in the rust belt so it accelerates wear. Don't let a shiney outside fool you into not paying attention to the parts that actually make the truck run. Just my thoughts.
I have had a '99 V10 F250 XLT for 11 years and have had mostly good luck with it. Although it has blown 3 spark plugs, but blowing plugs is not that uncommon for that year. It got around 13 MPG when I bought it back in '00. I haul a slide-in camper that weighs about 15K wet all summer and I get about 10 MPG on the highway and about 8 in the city driving to work. When i haul my boat too, it gets about 8 on the highway. Gas is about $3.65 to $3.69 for unlead in Anchorage vs about $4.08 to $4.14 for unlead. So it depends on what both trucks get for mileage as to which one costs the less to operate in fuel.