If your use to shooting real rifles... bare in mind that these things are 6mm smooth bore...man my ruger mini14 is a sniper rifle compared to these thing... and the mp5 stuff has rather short barrels, small batteries and mecanical issues with most brands.
You might want to consider a tm m4a1 (some guy is selling one for 350$ on AC)... use it for one year and if you dont like it, you can sell it and get your money back... if you like it, truck loads of aftermarket parts available and they grow old gracefully...
For the pistol... try both green gas ans co2 version... again with your background you might appreciate the precision at range the 350 fps co2 vs the 315 fps green gas will afford you!
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