I've seen images of a lot of SureFlow pump based WI installs, not many had the water hammer installed but when I did see them they were directly attached to the pump out port.
This is what I have found with regards to the Aquamist accumulator "The accumulator does two jobs, it absorbs the peak pulses generated by the piston and stores it rather loosing it as back pressure seen by the forward moving piston"
I also found this during a google search
One of the first areas I concentrated on was the pump. As seen on the left, I got a water hammer (the copper cylinder) to minimize pressure fluctuations and keep the switch in the pump from switching as often. This fit right on the pump I got (once I bought a "T" anyways). I then has to install a reducer fitting to reduce down for the Aquamist quick-release line connector. On the feed line of the pump, I put on another reducer and a hose barb for connecting the supply hose
http://users.frii.com/maphill/wi.html
Also found this, has an image of a sureflow with an accumulator:
http://www.aquamist.co.uk/phpBB2/ind...9904e61f28ff6c