Quick change battery.
Did I mention Bullpup!
I got my B5 kit about 3 months ago. And I love it. It was very easy to put together and works great. I have had no problems at all. Its compact, since its a bullpup it feels light, and of course it looks just awesome. The guys at Identity Crisis did an amazing job on this. As they said it takes virtually every A5 mod that can be put on it. And it can still be field stripped easily. Not to mention 1 quick release pin and you can change the battery. This is an awesome MOD for the A5
I strongly reccomend this product. I know the price looks bad but if you look at what you get its really not bad. You get a E-grip with the APE board! It has a stock and shroud built in. And the look is amazing.