If you like your 05, with the 6.0, it is possible to make it as bulletproof and reliable as the old 7.3's. The modifications are all readily available in various kits, and the cost for the parts and labor run around $5000.00, if you do everything recommended.
Go to www.powerstroke.org
and check out the 6.0 section. They have a topic there about how to "bulletproof" the 6.0.
I am thinking of picking up a 6.0, since they usually sell at low prices, and having all the mods done to it.