It did OK in Russia (along with the P-39) but the Eastern Front air war was mostly tactical support for the Red Army. If the Luftwaffe wanted to shoot the Russians down, they had to come down to their level. Below 15-20,000 the P-40 was OK. A similar situation was in the Western Desert when they flew in support of the 8th Army. No good for escorting B-24's at 28,000 with it's single stage supercharger though.
Don't forget, the early Mustangs with a similar Allison engine were relatively lack lustre performers.
I still think they look good with the big chin under the nose. Especially 112 Squadron's with the (first) sharks mouth decoration.