I bought some cheapies a while back (made in India I think) and they are garbage.
The taps and dies I bought through Chronos were high quality, cost more and are still churning out decent threads years on. I can be a bit hard on my tools at times but these little fellas just keep going. 'Ya gets what ya pays for in this world' ,it's the age old story so if you are intending like me, to do lots of work with this type of tool, bite the bullet and shell out for some proper ones... you won't buy a cheap one ever again!
If you intend using them on steel, you will definately need decent gear but DO buy a bottle of Rocol cutting oil as it will transform your thread cutting and stop you from breaking taps, again, not cheap but it will last you for years as you only need a drip for each job and coupled with that, what price a broken tap!. If you cut a piece of steel with a dry hacksaw then try the same job with the cutting oil you will see what I mean.
Hope this helps.
Chris