Sim-4 with bi-pod, suppressor, sight, extended sight rail, mag feed port, remote, and E-Trig.
Accuracy, rate of fire, look & feel.
Breaks and out of box condition.
First, the Sim-15 and Sim-4 and basically identical, with the exception of a few slight differences that really don't equal the cost differences> go with the Sim-15. For the complete listing of differences, go to the Ariakon website, here> www.ariakon.com
The Sim-15 is highly accurate and refined when using correct paint (RPS premium is my choice) it has a high rate of fire with the E trig and electronic hopper ( I would suggest the electronic hopper all the time) It looks very cool and always intimidates people *good thing.*
However, I found the gun was basically useless out of the box.
I had several problems, which took time and effort, and money, to fix. Only after I fixed these issues did it start to work properly.
The feed neck snapped (cheap plastic, metal on Sim-4)> $15.
The feed bend snapped, twice> $10
The spring was to tight, velocity 380 fps, low velocity spring> $10
When I opened it, I found the velocity screw was stripped*> $20
The connector pins wouldn't stay in, Ariakon said Sim's somtimes have that problem> I fixed it myself, but Ariakon will do it for $25.
In all, it cost an extra $80 to get it working, but it's eventual performance makes it worth it.
* The stripped screw possibly could have been my fault.
Pretty good marker, however I would probably go for an upgraded A-5 by Tippmann given the chance to do it again.
Recommended for someone with time and money, and who will put care into maintenance. Also, someone with access to machining equipment and know how.