I ran the Mt 43 on my 04 KTM 450 exc(the bike in the pic) for King of the Motos. The rear tube is a standard light duty tube ran at 5psi with no problems. I now have 178 miles on the rear, all Extreme Enduro stuff. This even includes 35 race miles. It looks like I will get around 300 miles out of it!
The only time the front Trials tire really comes into play is on the steep downhills! Being able to have the tire stick and me just having to work on the front brake gives me confidence. With a knobby not so much. A lot of the Extreme Enduro guys run a knobby front and rear. I will take all the help I can get with the Trials Tires!
The KTM or Burg 300 is my next bike for doing this kind of ridding. I believe it's the ticket! I laugh because I was the only racer at KOM on a dual sport street legal bike! I hope to be on a 300 for next year! Long winded, but hope this helps!