It's the actually possibility of getting them with certain classes...and any control over getting screwed by randomness. As an invoker, necromancer or conjurer if you can't get your wands....well, you suck (or you got the few spots that are absolutely atrocious like a fucking dragon lair). You can also easily fight without a/b/s with those three classes specifically so there's really no room from complaints in that area. If you're a transmuter who happens to get an undead mob or an anti-paladin with all but 3-4 spots, you're pretty much fucked. Saying things like "beg/barter/group with others" isn't exactly viable for a lot of people, nor should it be. Non-sleeks are also hoarded by every hero mage that is fighting over them because almost none of them can even find their wands....and the smarter players sacrifice it and get it again so there's no shot at a loss.

And on the flip-side, you have deathblows landing for unspeaks with zero work. Or you can just get ganged down or outdamaged by the ever upward scaling damage over the years when protections have gotten harder and harder to get. The game is mostly shifters and warriors because both take nearly zero prep/work in comparison for the same output....and I'd venture to say warriors have gotten nothing but stronger over time.

I could go into it further but honestly in a shitty mood because of the current hero groups. You want to see the flaws of a/b/s? Play an anti-paladin.

*** And don't say "APs can have a bajillion charges!" because that logic is flawed beyond belief in this argument.