Considering the horrendous casualties the Red Army faced in the beginning of the German invasion, I get the impression that the "original" army was all but wiped out by the end of Operation Barbarossa. Is that true or a misconception?
With other words, was the Soviet army of say 1943 basically made up of completely different soldiers or were there many veterans from the beginning left?
The Wikipedia entry on Barbarossa says that of a total Soviet strength in theatre of about 5.5m, of whom just under half were at the front line, about 465,000 were killed in action, 235,000 killed in accidents, illness or other causes, 101,000 died of wounds after evacuation and 2,335,000 "missing in action".
It's really really difficult to kill that many people, and the Germans would have been stupid to try some sort of meat grinder tactics because the Russians had essentially limitless manpower. So with their blitzkrieg tactics, what the Germans did - repeatedly - was attack in two places, advance, swing inwards and encircle a big mass of Red Army soldiers. Then do it again, and again and again. 465,000 out of 5.5 million is not actually that many killed in battle - but 2.5 out of 5.5m taken prisoner is massive. The Germans took so many prisoners they almost didn't know what to do with them all.
So, to answer your question - your chances of surviving Barbarossa were actually pretty good, but more than likely you'd be looking at a German POW camp for the rest of the war and they didn't treat their Russian "subhuman slav" prisoners that well. For that reason, the Red Army of 1943 would, yes, have been made up of mostly different human beings (especially since most of the senior officers responsible for Barbarossa's failures were sacked and/or shot).