Wheeleez cart for Hobie Outback

[OpenWater]

I'm considering buying a Wheeleez Beach Cart to move my Hobie Outback around. Does anyone know if I'll need the optional Wheeleez Rail Kit to stabilize the Outback?

Also, is it possible to swap the wheels on this cart between the large grey beach wheels that come with it and the black foam-filled wheels (which I'm guessing would be better for using on hard surfaces)?

I'd like to be able to switch the different wheels back and forth so I can use whatever wheels work best on the surface I'm pulling on.

Thanks in advance.