I own a YJM Sig Strat and its amazing to play and hear I also own a EBJP6 W Piezo. So I have and know the best of both worlds. The YJM has low output pickups and the brass nut and the scallops all add to yjms tone. In interviews he has said that the strat is the perfect guitar for him. The shape and the pickups and the hardware its all to his liking. Plus he owns alot of guitars that arnt all strats

So thats just his thing so good for him. As for Jps EB thats also an amazing guitar but its pretty damn different than the strat in almost everyway, but not in a bad way at all
I think it would be weird to see him playing a Silo or an Axis. Almost as weird as seeing Vai with an LP! That would be ****ed up looking.