I did this comparison a few years back, but forgot to put a date on it. Regardless, it's a comparison of one of the cheap (under $5) Harbor Freight meters to an HP digital voltmeter. Except for resistances under a few tens of ohms, it did quite well. I don't have my HP meter calibrated, but it agrees with my Fluke differential meter within 10 ppm (and a precision HP power supply); both are awesome meters.

I believe SgtWookie said he did a similar comparison to a Fluke calibrator and got similar results.

The bottom line is that you simply don't have much of an excuse not to have a digital multimeter if you have access to a Harbor Freight store.

Note that CenTech is a Harbor Freight brand name.

 

Those cheap meters are nice.

And they're fairly rugged - I've measured 230V mains on the ohms range with no explosion, and it still worked okay after it.

Only one problem. I dropped one off my bench and it didn't work any more. So they aren't as rugged physically, but you're not going to get much for £3/$5.

 

I've pulled test leads out of the probe tips. I just keep a pile of them around as they often go on sale for $2 - $3