Russian aircraft are built like the proverbial brick out-house. STRONG, ever-lasting. BUT, that of course has it's downside - extra weight, meaning greater FBO's, lower freight uplift (depends on the aircraft naturally!). Russian designs may seem cruder, and less refined, but work darned well.
As Ghengis said, Russians tend to reverse engineer existing designs, and adapt as required - ever notice how many of their airliners look like existing western counterparts - Tu144 (concorde), 154 (727), 334 (F28 / 100), 204 and 214 (757), 134 (Dc-9 ish), Il62 (VC-10) and Il86/96 (Airbus) are prime examples!
They may not have the refinement of Western designs, but NEVER denegrate them based on structural strenght.
Kind of remind me of good old Douglas aircraft in fact!