In Chris's defense, he did say that he feels the Z IRS in particular is a little dated and not as efficient as others. I would think the Zs suspension design is not so bad considering how many SCCA championships it won. So he never said that a well engineered solid axle car is just as good as a well engineered IRS car. He just said that not every IRS car can outhandle a Solid rear axle car. Which is true, but its not a black and white answer. I did make some sweeping generalizations, and for that I do apologize. I fell victim to low brow, lazy posting, which I am usually careful not to do. Sorry. I will concede that there are probably a few live axle cars out there that can outhandle a portion of the IRS cars. I would wager that those cars had many dollars of development into them. Its never a one to one when comparing cars. And since there is not one brand of car with both a solid rear axle and a IRS setup as an option (other than that Cobra, right) any direct comparison is sort of apples to pears. Next point, you mentioned that all the cars I listed are mid engined. Is the arguement your making that if they had a different layout F1 cars would use a solid rear axle? I would think that cant possibly be what you meant by that. But assuming you did,lets take the BMW. Uber dollars of development and not a single live axle car in the bunch. Surly if they could post better numbers they would use one. But they do not. Neither does Ferrari, Porsche, Lambo, Mercedes, every super car in the world, etc. Lives axles are in the same boat in my opinion as pushrod V8's. VERY effective and reliable (i.e. LS1), but dated technology that is past its prime. Both of them can be made to work very well in different applications, but both have been replaced by better designs. To sum up, I did not say IRS is the ONLY design that will work. I said IRS is the best design. A live axle will do the job adequately but its not the best solution for the highest level of handling. I just dont see any way that statement is wrong.