Does anyone have any advice on mobile forges? I have one at home, but need one for my rig. I've heard everything from the vibrations causing liners falling out and gas leaks to just downright poor quality to start. I'm leaning towards the NC Whisper Lowboy, but does anyone have some guiding advice?

Might try looking at some of the farrier blogs, as we are the only fools to throw our gas forges in the back of a truck. Might as well by a liner kit now, as they really don't hold up well to vibration. A dab of silicon or stove cement between the shell and liner helps as dose a dab of stove cement between the liner bits (very thin or the bits won't fit in the shell. I've mounted my Proforge on vibration dampers, and cemented it to gether and it has helped, but the truth is, it still wont last for ever do to vibration in the truck, or coming soon, the trailer. Actually I'm considering going old school and adding a side blast to the tung of the trailer.
And don't forget, paint on one of the reflective forge coatings, it will boost the efficiency and keep flux from eating up the liner and fire brick shelf.
And if you plan to forge in cold weather, or for extended lengths of time, forget about the barbecue cans, get a pair of 100# bottles, dunking a can in to a horse troff or your qwench bucket to get the presher up when it starts to ice up sucks.
And as a final not, when I asked pro forge for advice on extending the life of my forge liner, they said not to put it in a truck or trailer! So much for costumer support.

I chose a whisper daddy  and it worked wonderful in truck and also for ornamental work at home...I no longer shoe but use the forge at home a lot. I have used several different brands and it fit my work the best. Three burners get it up to temp fast.

check out Mankel forges, Tim Carr sells them now. I'm running the one i bought in 1974; on it's 6th liner

A second note, gas forges are hard to isolate the heat, so plan on selective quenching, and if you primary goal is general blacksmithing, you may whant to cunsider multiple forges, 2 or 3 burner for big or oddly shaped peices and a one burner for smaller more isolated heats. Even a micro (I brick) if your working small peices all the time. Costly but much more efficient of fuel. Most folks resort to a oxy/accetaline or oxy/propaine rosebud for isolated heats and fore shapes that won't fit in the forge.