I would tend to lean towards a swiss, unless you got your hands on a really good Jersey. The swiss will outlast the Jersey, they have strong feet and legs, they are rugged. Swiss are also a dual purpose breed of sorts. You could breed a swiss to a beef, and end up with something you could slaughter. The one down side to swiss, is the fact the calves can be very tricky. The trick however with them, unless you choose to let the calf suck, is to take the calf away as soon as its on the ground. Swiss do have a big appetite, but so do some Jerseys. We have a Jersey that eats about as much as a holstein and she tested in June at 74lbs, then here a couple days ago at 68lbs. She is only getting 10lbs of grain a day. If I went balls to the wall with grain (20) she probably would up to 80. She over conditions, simply because she eats wayyy too much.
We have a swiss, she didn't produce heavy, however swiss do take a while to reach their peak. It isn't uncommon for a swiss to go to 12-15yrs of age, and still be milking.
If it were me, I would buy a swiss. I could breed it to either a swiss bull, or simply breed to a beef (angus, hereford, etc) and have something to eat. The swiss we have is very gentle.
Jeff