Highest res tends to be on Patreon. FurAffinity has the most of my art since that's where I started posting.
I haven't posted much of my MPP on my other art sites.
Pledging 3 bucks and rummaging through the Patreon is probably your best bet if you want the highest res! Then check my FurAffinity for oooold stuff if you're curious. ( like from 2013. )