I was tempted to get a digital level, but the clerk said that if it gets broken, it's totally gone, so he prefers to keep tools simple.

I am also wondering about the worth of rolling measures.

Hi,
Anything that is broken is broken! I had a real problem with digital voltmeters since they would not test a capacitor. Either one is broken when broken.
I do not see the reliability of a rolling measure since it is as accurate as the traction it gets. More accurate is a proximity measure.
Peace,
Clarke