I recently purchased Zipfits World Cup SE liners 28.5 size (which is the same size as my ski boots). I am wearing 11-10.5 size in regular shoes.
I tried them on, laced them snugly and I see bulkiness generated in the area where the toe box connects with the tongue around the first two front lace holes. I do believe though that this is the right size, since my toes almost touch the front on the liners.
Please let me know if this bulkiness is a usual occurrence or I should try a smaller liner