Agree with others that bits are "supplies", not "tools."
We were happy with bits we bought from
MariTool this year. I also personally bought
this index from Aircraft Tool Supply to have a set at home.
Reducing the number of fastener sizes helps you reduce the range of bits you need to maintain. We ordinarily use #8 machine screws, with occasional use of #10, #6, #4, and 1/4" screws.
These bits we buy in quantity, as we will use up several of them in a build season:
#16 (free fit for #8 screw, our most popular bit by far)
#7 (free fit for #10 screw)
These bits we have a couple of each:
#25 (free fit for #6 screw)
#30 (free fit for #4 screw)
#29 (tap for #8 screw)
#21 (tap for #10 screw)
17/64 (free fit 1/4" screws)
Note that there is only one fractional bit in the bunch.
I plan to move to
this container for storing the common bits next year.
We have
one of these that is filled up to 3/8" for miscellaneous tasks.