Robin, If I remember correctly you will be with the crowd at Ferintosh. With a crowd as diverse and esteemed as that, I'd wear the MacLaren 1819. Mostly because no one else at the table will be wearing the same tartan. Porrick will likely have that great looking Murphy tartan kilt, P1M has many fine kilts to choose from, Freelander and Sten Rune will have some nice sporrans for show, and Hamish will likely do a costume change at different intervals of the meal etc, etc, etc.

Someone else will likely have the Xmarks tartan and the Isle of Skye tartan, so I would save those for the pub crawl instead.