If you can see properly when not reading then get large monitors (47 inch or bigger TVs) and put them 5 feet plus away from you. You won't need your reading glasses to see these and can work with them all day. Get real reading glasses (they're cheap) for when you do read.

That's called corruption. I have a $900 device that can stop at 0.01mm. D.C. has a subway systems that costs billions and they can't stop within a foot? This isn't the 1800's. Just your average crony capitalism at work.

It depends on how good your skills are with the DSLR. If you just point and shoot, then maybe no difference at all. To get the most out of your DSLR, you have to know what you're doing and how to do it. Handing a $1,000,000 dollar violin and a $500 dollar violin to a beginner produces the same results.