For towing you cannot beat the diesel power, the torque just can't be denied. The added cost of the diesel from the factory is there, the extra maintenance cost as well. From a money stand point they cost extra, but if you plan on keeping one for a while you will get that money back on resale or trade vs a gas truck. Emissions is a problem, but there are delete kits. If you use a diesel truck right, your chances of having emissions issues are slim. They are made to work not drive 5 minutes to your office and be turned off. If you have one with emissions, you have to run it and use it. If it sits and idles or doesn't get up to operating temp, your gonna have some issues.
I have been in a diesel for over 10 years now, and will never go back to a gas. I get way to good of mileage, have 500hp/1100tq at the rear wheels to tow, have tons of room in my mega cab, and have had ZERO issues out of either of my dodges. The front end problems didn't get me on my 2006 and so far so good on my 2014. I do enjoy my wifes Yukon XL with a 6.2 gas in it. GM's 6.2 is no joke in the power department and does unreal on mileage for a school bus, but I like the torque, I can't lie. Go drive some trucks and see what you think, look for rebates, sales, and financing specials if you go that route.