Do not use a trim head screw... use regular head. I use a combo drive... square drive almost never strips out, but it is only "standard" in Canada, so the combo allows use with a philips head driver if necessary in the future.
MdFeeleys and CS Hardware have combo head, type 17 (self tapping) high quality screws - I usually pay around 2 cents each in 1000 lots, rather than 5-6 cents in 100 lots.
Whatever you do , don't buy Home Depot screws... they have a special feature to train you in the use of new, adult, colorful words as the shear off in the most awkward position (I have never had a square drive CS Hardware screw shear, and the only stripped heads I have had are when I am reusing a screw 4-5 times.
Star drive seems to be more popular in North Central US, and are pretty good, but I have less experience with them.