Advice on Tires?

So my Lexus LS400 is in need of new shoes and I've been looking at these Sumitomo HTR ZII's on tirerack. They're extremely cheap ($68 per tire) and seem to have some decent reviews.

I was wondering why anyone would buy $150 tires when there are tires like these for half the price. Does anyone have any good or bad experiences with cheaper tires? Any recommendations for tires? I'm mainly looking for the best performance summer tires since I live in California and All-Seasons are absolutely pointless.