To summarize my feelings towards this square: love it when looking at the pattern book's photo, hate it when knitting it, love it again when looking at my own finished square!
If you don't like grafting and weaving in loose ends, maybe you should consider carefully whether to make this square. But it is a good challenge. Besides, I really love the Celtic knot in the centre (a cover decoration on Alice Starmore's The Celtic Collection, according to the designer). So, something unusual and unique always comes with a price. The zillion loose ends can really drive one crazy!
It would also be a good idea to leave this square for the later stage of the project when you would have a better idea how you tension works out with the needles and the yarn. The measurements of the centre square is not given, so I was a bit in the fog as to how my gauge worked out. But after working for so long with the yarn and other squares, I did have a rough idea.
Now, I am on to the last square!