neither are better for production... its personal prefference... there are pro's and con's to both

but i couldnt envisage taking the computer i use for my production out of the house never mind to a gig, so i would never personally ditch my desktop for a laptop altogether, not a chance.... id just save and get both, just upgrade the memory and HD if u want the machine to run better, or check the settings in ableton and ur computer, increase the virtual memory buffer etc etc