The 6.0 Turbo Diesel is an option on a few of the BT Cruiser including the 28'er. That one appears to be built on the F450 platform as versus a couple of the smaller BT's which are on the F350 platform. Both platforms are excellent for a rig this size.
I find that 5250 and 5270 model to be quite attractive, partly because of the platform, the layout, and partly because of that engine option.
With a Class C rig in the 27' range, you are going to have ease of driving in traffic and a lot of options available to you as far as boondocking or county/state parks which often have smaller sites. This can be problematic somtimes for the 40' 5er being towed by a extended bed dually. Sometime however, in your process of determination, sit in a rig similar to the one you are eyeballing and also then sit in a 30' 5th wheel. Sit in it for an hour. (If the saleman at the RV lot bugs you, point to the door and ask him to get out.
) You guys are going to be spending a fair amount of time 'seeing the USA', make sure you get the rig that you will feel comforatable driving AND living in.
And just to make sure you have a WHOLE LOT on your plate (
) are you thinking generator yet?? and if so how is that conversation going??