[The Saint]

The Sorbothane cushion is suppose to do the same thing as the Systema silent piston head and cylinder set at a much lower cost and complexity.

The hotter the spring you use, the more stuff you'll have to swap and the greater the chance of something failing. Not to mention it'll decrease your ROF. One basic rule to upgrading that you haven't seem to learn is that, all else being equal, you increase fps first by increasing air seal efficiency, not but simply tossing in a hotter spring. You might be better off finding someone to do this for you.

You'll also need to change your bushings to metal ones, if you still have the stock bushings. And replace the hopup bucking, too.

Finally, version 3 is plenty tough if you upgrade correctly.