I personally think thats like comparing apples to oranges. Buick and Chevy are both part of GM. Thats like saying Cadillac and Hummer have things in common. Obviously Lexus and Toyota are similar because most of what Lexus makes is based off of a platform from their parent/sister company Toyota.
I feel comparing Honda and Acura to Lexus and Toyota would be a more fair and even comparison.
well buick to chevy is almost like comparing GMC to chevy or Cadillac to chevy. They are different brands but use the same tech. Escalade vs. tahoe type thing.