Swiftech MCP 35X

[Erklat]

Since WL stated that old types have only rpm sense, you're left only with wire tricks.

I'd get 3.25. I doubt they are noisy. It boils down to whether you are sensitive to the high frequency pitch they produce which
might get emphasized with the dual top. Each pump with dedicated top provided like quieter solution. There was this bloke from
Luxembourg who stated he ain't going to dual tops anymore back in December.

So as I see it:

pros: PWM controllable thus potentially quieter, custom top is no longer a 'must'
cons: no real performance improvements, absolutely ridiculous price, there is a chance custom tops will still be better.