Hi mteNoods are you after standard metric or imperial?
If you already have a tap holder and die holder then what about building a set of the sizes you will use probably m4, m5, m6, m8, m10, m12 ?
If you don't often use blind holes you could start with 1st & 2nd tapps and add plug taps as required.
Depending on what materialy use use you could also look at spiral taps.
Might be worth a look at cromwells and msc and see individual parts compared to a boxed set.
Will be interesting to see what the others recommend.
I have only used known brands from industrial suppliers and never had a duff tap or die, unless on a production run we normally get yearts out of ours, probably need to get a few soon.