I agree with Gaudion , especially about the pvp aspect. Having the extra armor might be the difference between death and shocking the last of that rogue's life away.
The only time I would advocate a 2h over a 1h + shield is if the overall bonus does lean towards the 2h due to it being a large upgrade vs the 1h + shield you may be carrying. This is only relevant in PVE where you shouldn't be taking damage and the loss of armor isn't going to be a huge factor.