I'm having the numb toe issue too. I hate to give up my Specialized taho's, I love them and I can walk in them.
I was going to try an insert with some gel in the forefoot area. Has anyone tried that yet?
Are you riding the road bike with the Tahos? These shoes have a lot of flex in them compared to the mtb race shoe. You might want to take a look at these or these. I can comfortably walk in them and use them as my road shoes. I wear the Tahos for mtbing.