Apex bits are in the 'perfectly acceptable' category! Certainly way ahead of the Taiwanese offerings you find!
Zephyr are a frac better, if you look at Zephyr and Apex side by side, especially the larger sizes, you can see that the Zephyr are slightly better made.
PB Swiss are probably as good as Zephyr, maybe even a notch above again!
in a former life I used to do a lot of repetitive assembly work, and if you're putting in machine screws in batches of 200 you pretty soon find out which bits are up to it and which are not.
The first thing you need (assuming you are using a decent quality fastener) is a well fitting bit. All other things being equal, a poor fitting bit will allow a little movement and wear much faster than a decent fitting one! You then need decent steel, properly treated, and some sort of decent finish as well!
In order of quality, and durability (not quite the same) I'd rate the major manufacturers as follows:-
1) PB Swiss. - Best made, most durable, superb in every respect! Only downside is that they are biased to metric, so while you can get short 1/4 inch bits in inch sizes, you are struggling with some of the others! First choice for metric screws!
2) Zephyr. - Accurately made, nicely finished and durable! I was once assembling some awkward cap screws that needed small hex bits. I was breaking Taiwanese bits like you wouldn't believe, and even the Wera bits I'd got for the purpose! Thankfully I had one Zephyr bit with a Snap On bit driver and that finished the job without problems! First choice for inch size screws! These tend to be used a lot by the aerospace industry, both U.S. and British!
3 Equal ) Wiha. - Good quality German made bits. Nothing wrong with them, just not as good as above makers! A lot of British factories use these.
3 Equal) Apex. Good quality U.S. made bits. Again, nothing wrong with them, just not as good as 1 and 2! I've seen these used a lot by the U.S. military!
5) Wera. Some folks rave about these, but if you talk about their experiences you generally find they are comparing them to Taiwanese or Chinese made bits. Sure, they are a vast improvement on those, but I've found the other bits listed here to be a better still!
Hope this helps!