I didn't play much of vcoh, and when I first ever played coh2, I just liked Ost more than Soviet cause Ost had bunker and their mg had a wider arc lol!!
But really, I now like Ost more than soviets simply because they have much cooler units. Like compare grens with their nice looking uniforms with conscripts with such ugly looking outfit and some linen around the back! ;P
Or Panzer4 vs T34, or Mg42 vs Maxim, or in general all soviet tanks look immensely ugly to me (specially the ISU ;P) or Ost units never ask for vodka after they're finished with capturing a territory! haha
I really don't care which faction is stronger, that's the only reason for my preference.
Having said that, I really like the British faction (probably the most among all factions) since they have some super cool units and I think they have the coolest unit voices of the game, specially the AT sniper with its awesome Scottish accent, that's my most favorite unit in the game!