Which one of these 2 machina decks should i run competetively?

The first one, but you should make a couple changes. In that first deck, I'm uming you're using Machina Force as discard fodder for Machina Fortress. That being said, you should also include a couple copies of Shredder, which is a handy lvl 4 machine that helps keep your opponent's field clear. Machina Peacekeeper is pretty useless, so I would ditch those. I would also recommend losing your Dimensional Prisons and replacing them with Royal Oppressions. I think you should add 1 more copy of each gadget, and get rid of a copy of Machina Armored Unit, Solidarity, and Smashing Ground, because it seems like your hand could get clogged with spells.