I'm sure the large 8mm square profile is fit for the job, but when was the last time you were served tikka or kofte with such a large whole in it? 
I dont notice the hole with these flats Malc. I can thread each piece of meat 3 times quite easily, although it can be scary ;D (always in fear of self inflicted stigmata)
Actually, why am i threading them!! I just need to slide them on whole. :

Speaking of holes, When i used to buy kebab rolls from Deans in Croydon, they would ask if you want it hot?
Of course! ;D
They would then push 3 fresh whole green chillies into the hole of each seekh kebab