Milo was a big baby (10lb04oz at birth).
After a few weeks the smaller wraps were just useless.

100x100 and 120x120 were the easiest for me to find, but it was at baby shops

pumpkin patch, bubba blue, living textiles and there was one more brand all make the 120x120 muslin wraps, and they were nice and light, and stretchy.

Milo was wrapped til about 5 months.

I also found interlock stretch cotton was good, I got a few metres at spotlight and just hemmed the ends.