Agreed on all points Cory said. I have a cheap import 6" digital that is actually my primary caliper. I got it about 5 years ago for less than $20 and other than batteries once or twice a year it's still doing great. But, I take care of it. I've purchased other import digital calipers more recently from Harbor Freight and I don't like the feel of how they slide, and I had a couple that were about a thousandth off on measuring half an inch. But, honestly you'll probably be just fine with any other sort of cheap import digital caliper, from VXB or Little Machine Shop or Amazon or wherever.
For quality, I too like Brown and Sharpe. Very very smooth and accurate, but expensive. Too easy for students to ruin expensive tools like that.
There are instances where a dial caliper is preferred, such as measuring to see if something is out of round, because the cheap digitals lack on display update speed. However, the digitals are easier to read.
I'd stay away from vernier calipers. Talk about an instant drop in work efficiency. I used them once and never again. I had a professor with a PhD that couldn't figure out the darn things.
