flexiteek and aikona are made by the same company Aikona is a rigid base with a thing flexiteek top layer, and is designed for long straight runs. I have laid both aikona and flexiteek, Both get very very hot in strong sun , in the med my aikona/flexiteek will burn my feet, whereas the GRP is fine. Aikona seems to be slighly cooler then Flexiteek. Aikona cant really be sanded as its not a continous solid, however really both Flexiteek and Aikona can not be sanded like a conventional teak deck
Despite what the blurb says , they do stain and some stains can etch into the top surface and can be very difficult to get out ( rather like teak,). Also dirt tends to get pushed into the surface layer and again like teak can be difficult to get out , though agressive power washing
does shift most of it.
If you varnish
it it looses all its non-slip properties.
I remain of two minds, its not cheaper then real teak, and if you are laying it piece by piece its only about 30-40% faster. Heat joining and bending it require an industrial quality heat gun the DIY types cant provide enough heat.