What you pay
The Vitamix 5200 runs about $599, the Blendtec Total Classic about $549. Close enough that performance decides it.
Blending and warranty
The Vitamix blends thick batches more consistently, runs on a variable dial, and carries a 7-year warranty. The Blendtec is strong but its warranty is shorter.
Footprint
The Blendtec is shorter and lighter at 15 inches and 7.28 lb, and fits under cabinets the taller Vitamix won't. The gap is consistency and longevity against size and a slightly lower price.