Finished another project today, wanted an MP5 like this for ages.
This one is an ICS MX-5P. I've short stroked it, added an Aimpoint Comp M2, rail and G&P foregrip (hardly any modification required). The G&P light takes surefire bulbs, so I fitted a 200 lumen LED.
The only thing about the ICS I thought was poor, is the plastic flash hider. I replaced it with an ICS metal one that also has a thread. Got a 28mm extension which allows a tracer unit to fit.
Getting mags to fit is also a problem with this model. I couldn't find much info online as to what would fit, in the end I bought some Cyma 120rd midcaps as they were cheap. They have to be filed on the sides at the front before the cutout. Had to file them down from 22.8mm to 22.5mm, they feed perfectly.
Getting a battery to fit the tiny space in the foregrip was an issue. Component shop helped me out with an 'aircraft pack', 1000mAh 11.1V , here's a link if like me you've been struggling! http://www.componentshop.co.uk/11-1v-1000mah-35c-continuous-discharge-lipo-battery-with-jst-connector.html