Best budget micrometer?

Most Japanese service manuals spec's are in millimeter's, but you can pick up a inexpensive micrometer from Harbor Freight

Get a 6" dial caliper.

I bought a Swiss made Brown & Sharpe dial caliper just like this one about 20 years ago, and it's one of my favorite tools in the box.

http://www.ebay.com/itm/BROWN-SHARPE-599-579-4-Dial-Caliper-0-6-0-0010-…

As with any measurement tools you should be using a gage block to calibrate your measurements prior to measuring if you are looking for a measurement that is withing a couple thou or less. You typically try to use a gage block in a similar length to what you are trying to measure so you are calibrating in that range. You take your measurement of the block vs the calibrated length of the block and that is the error you need to add or subtract to your measurement.

I agree with Cam in the I also prefer a dial caliper to a digital, but some people have difficulty reading manual tools. If you are one of those people you are likely going to make more errors with a dial caliper than a digital.

Are you referring to a digital mic or digital calipers? Mics look like a c clamp and micrometers look like a ruler. Good digital mics often have the non digital marks as well as the digital display. As a general rule, calipers aren't as accurate as a mic. Calipers are especially bad at doing ID measurement. They also have adjustment to keep them from rocking which effects their accuracy. If you can justify it, get good tools like Mitutoyo, Starrett or Brown and Sharpe.

The article above was interesting but he was using a bunch of junk calipers and a junk digital mic. For most stuff, that will work fine but for doing a trans, you would be better off buying either good new digital stuff or good used manual mics from Ebay. If you stick with one of the brands that I mentioned above, you will be in good shape.

I would buy a Starrett.

Cheap and accuracy shouldn't mix. Like BAMX said, Mitutoyo, Starrett or Brown and Sharpe. I use these at home and work all good stuff. I would recommend getting a caliper and a micrometer. Knowing the part is good and in tolerance is a piece of mind for me.

I have a bunch of antique Starrett calipers that belonged to my grand father. They are still spot-on accurate and pushing 100 years old.

I bought a cheapie digital caliper from HF. I don't think it was worth it. I can't get the zero to reset. I can take a measurement then close it down and don't always get zero. I get like .005 if I don't get zero
I bought it for reloading and I don't really want to be .005 off on my case length or cartridge overall length.

MM to Inches conversion: Multiply MM by .03937

Example. 25.4mm x .03937 = 1.0"

your old school micrometer has everything you need .... you just need to be able to read it .

Digital calipers with 2 decimal places are ok for farm work , but for diameter and width, a micrometer is the thing to have, you dont need to spend a bunch of money either