I wouldn't use artificiall sinew, it is vastly over rated.
Sinew makes a nice wrap and can be done neatly if you use long strands, I use thread because it is quick, I wouldn't have been able to do any sinew wraps in the field at tournaments like I did with thread because of the curing time and not having the materials on hand.
Here is one of my sinew wraps, it is probably stronger than the thread wrap. I did try to stretch the wet sinew some before I wrapped the bow limb. I probably used backstrap sinew for this wrap, longer strands of leg sinew would work just fine.