I have 2 kilts each in these materials:

* the standard Marton Mills polyester-viscose

* a 10-11 ounce wool-polyester blend. One of these is from Fraser and Kirkbright, and I don't know the weaver of the other material.

Upshot is that there's no discernable difference. They both work well, they seem to have similar degrees of "toughness", the swing is comparable and so on. From a "make a kilt" standpoint, they're not appreciably different. I've hand-sewn an "8-yard" kilt out of 11 ounce 100% wool and it was a bit nicer than the blends but not hugely so.

They're different from 13 ounce and 16 ounce wool, so don't expect them to be the same. Some people revolt at the idea of the lighter weight fabrics being made into a kilt. Personally, I wear mine all the time, and have the material for another one sitting at home waiting to get made into a grand 6-yard Lindsay tartan casual kilt. For formal occasions I wear one of my two 13 ounce tartan kilts, but I live in my lighter weights kilts day in and day out. I've had the PV MacNaughton kilt for two years, worn it on an average once a week and it's still going strong, though it's starting to show a bit of pilling under the sporran. However, the pilling issue with MM poly-viscose is nothing compared to the pilling issue with acrylic fabrics.