The 110 did outclass the P-40 in BoX a few versions ago.
These days this isn't true anymore. The P-40 is clearly superior to the 110E-2 and it holds it's own against the 110G-2, albeit just barely.
I think the biggest issue lies in the familiarization with the plane itself, and this might have played a role in that RAAF fly-off as well.
In BoX the situation is this:
In the P-40 a "newbie" pilot has his hands full with managing the engine all the time, and when he enters combat, he will either give too much attention to the engine (and therefore lose combat), or he won't give enough attention to it (and therefore kill it, and lose combat) or he'll decide to stay on the safe side concerning engine settings (and therefore lose combat, because he'll cut the available engine output power by some 30-50% safety margins).
The "old fart" pilot who has scored 100 hours of flying experience in the P-40 already, will just naturally adjust all engine settings by bums feeling without wasting a split-second of his precious attention to it, so he'll win the fight because if used properly, the P-40 simply outclasses the 110.
For the 110, both "newbie" and "old fart" pilots just don't give a damn for their engines, they'll slam the throttle forward and backward at will, and anything will be set automatically for them.
Now that 99% of BoX pilots never take the time to familiarize themselves with any given plane, let alone the ones which are slightly more difficult in their handling, you will always have to take comparisons of these planes like the P-40 with a grain of salt, since it's very likely that the pilot who's complaining about it just didn't take enough time to learn how to handle it.
Take myself as an example.
In the beginning I've been complaining about the P-40 forth and back, but looking at our server stats I have sorties on it where I've killed 12 enemy fighters in one single P-40 sortie, of all kind, 109s, 110s, 190s and Macchis.
There's no other plane where I'm able to score as many kills in a single sortie like with the P-40, for the simple fact that it carries plenty of ammunition (4x cal 50s with extra ammo that is), it's sturdy, it carries enough fuel for longer sorties and it will bring you back home even if you happen to walk through your opponents line of fire by mistake.
Cheers!
Mike