Definitly Viable.
That depends a lot on the build of your army to be honest, but I dont think that you will ever pay a game with dwarfs and say, man stunties really blow against (insert army here) Unless your opponent somehow tailored a list, which is difficult against Dwarfs.
They can play differantly, I play as solid hard as nails blocks of troops, backed by war machines and some suppressing fire. You can play all or mostly melee, or all ranged, however you want, they are all viable.
To start get the battalion, one of the best battalions as it actually contains units all dwarf players use. Then decide the direction you want for your army, do you want lots of guns and war machines with a little melee protection? Or maybe a solid line of combat troops with support? Dependind on your choice, the direction to take could vary, no matter what I would say, Battalion, Box of thunderers/quarellers (either can be built) , another box of warriors, and a character or two should give you very good, well rounded place to start, from there you can see what appeals to you more and take it in that direction.