Hi supnth,
my comments relate to the Fanatic Allwaves, I have no experience with Naish SurfSUP's, though I do own a Naish Glide.
I am 6'1" and 88kg and surf a 9'6" all wave. I have no complaints with this board, quality is good, it is light enough and surfs well enough for me. I generally surf right hand point breaks and varied beach breaks up to shoulder high. The Allwave performs well in these conditions and is very stable and paddles well enough for a SurfSUP. I would have no issue with recommending an Allwave to anybody except if you want a high performance board you may be better off going for a Prowave.
as far as Naish quality goes I think you may have come across a disgruntled person. I took delivery of my Naish Glide at Xmas and it has had heaps of use since then. In my opinion the Naish a build quality is equal to or better than the Fanatics, so I don't think there would be an issue there. Though DJ has several Naishes so he will be able to comment more.
Good luck.
ET.