the best what?
I grew up skiing the East and learned to carve on black & blue ice. Western snow makes every day Christmas morning. When folks out here say it's icy, I tell them "be thankful you aren't skiing in the East," because Western "ice" is just mild hardpack back East. As a general rule, I have yet to encounter any true ice out here, with the exception of morning conditions in the Spring, which can be very reefy and boilerplate... but all you have to do is wait for the sun to hammer the stuff and it's wonderful again.
I think that someone who learns good technique in the East -- especially in the tougher areas with steep, narrow, bumpy runs (MRG, Stowe) -- can come to the West and ski typical conditions with grace and speed. Powder is an entirely different universe and skiing it can be cruelly un-fun to one who knows only hard snow.
I think Eastern conditions can help you learn more precise edging control, but you certainly have to work at it. Eastern hop-skid mogul technique doesn't translate all that well to Western snow -- it's too much work and you tire quickly. But if you skied Eastern bumps by carving the troughs, you can translate the skills quite readily.
Who are better skiers? The ones who know how to listen to and talk to their skis, of course.