TB; the couple of guys that get the dairy steers and raise them up north of me do the same...take them to 800+ and then sell them. They usually have corn or some other silage to feed and many get distillers or brewers grain or something. The one is a former dairyman, and one is a mennonite. I am sure there are others raising some because they have a holstein ( and any other dairy breeds welcome) feeder sale about 4 times a year up in Harrisonburg VA and there are usually a couple hundred of all sizes there.
Aaron; if you have grass, and can buy a couple of dairy steers then yes, I would . If you are going to butcher them for yourself, then I would go Jersey, but I like the jersey beef. Fat is more yellow, some don't like it, and their meat is a little " sweeter" if that makes any sense but it is very tender and if a good sized and finished (fattened up) is marbled pretty nice. I would get something in the 6-700 lb range. If you can only get holsteins, I would go with something in the 7-800 lb size and with 4-6 months, will get up to a decent kill size. Smaller frame will put on some meat/fat quicker than larger framed for what you are talking about. They both will have good hamburger and steaks , like Rib eye, N Y strip, Filet, and sirloin will be very good to eat. You will want something that is not too fat when you get it, because if it has been on any amount of silage or grain, it will lose weight when it first goes on grass. Something that looks a little lean but not pot gutted will get on the grass and just keep on gaining. Worm them when you get them and make sure you give a blackleg shot just for cheap insurance if you give no other shots.