So, my experiments and currently OSR (AD&D 2E) group did a few sessions of Shadowrun. I ran one session and played in two others. I'd wanted to try SR because it has two mechanics I thought were interesting and potentially fun: opposed dice pools and stun damage.
But the game, as a whole, is really hard to run and play with lots of fiddly bits to it. I keep wanting to adapt those two things, though.
I think dice pools make the temptation to add lots of greebly little modifiers and bonuses to your system almost irresistable. The nice thing about the d20 is ultimately everything is a number between 1 and 20.