I see where both are coming from . . .
The xB isn't "cutting edge" modern technology, out-of-the-box. But, it can easily be "upgraded" to WRX levels fairly easily (suspension w/ uprated performance sways, front strut brace, and springs and shock/struts or coilovers, and power w/ a simple turbo) and w/o a gigantic cash outlay. Most of the cost would be the blower.
What Tony (name assumed) is getting at is this:
Compared to most similarly priced (new) vehicles, the xB is WAY above expectation. The handling isn't far off "real" sports car levels, even w/ the stock suspension of NO rear sway, mediocre springs, and rather hard tires. That is what shocked me when I drove the xB for the first time, and I'm "used to" a well-set up and corner balanced 90 Miata (a "real" sports car by any definition).
The xB "SHOULD" handle like a top-heavy econo-car. But, it doesn't.
The acceleration is in the mid-8s 0-60, the same as a Miata and not bad for under $30,000- not to mention actually being closer to $16,000-17,000.
So, if your comparing the xB to a "supercar" like a Lambo, Ferrari, Spyker or even a modern Porsche, there is NO WAY it could be comparable for well under $20,000. Those are $60,000-$500,000 If compared to a more "moderate" priced sports car like a Boxter, S2000, Miata, and several no longer for sale, the xB is closer.
Now . . . compared to a "classic" sports car, like a 365, early 911, MGB, Healey (big-6, 100, or Sprite), Triumph TR (any number), up to the first and second gen Miatas (and contemporary competitors), the xB can "hold its own" for a vehicle not DESIGNED to be a "sports car."
Now, looking at the PRICE range, the xB is remarkable for what you get.
I do think the rear sway should be standard, as should the strut bar. I understand the "softer" springs (for a smoother ride), even if I would prefer the TRD ones as standard.
So, it depends what you are looking at when comparing the xB2 to a "high performance" car . . .
Compared to expensive, cutting edge technology, it isn't. The parts cost more than the entire xB.
Now, compared to the "seat of pants" experience, acceleration, braking, handling on mountain twisties, and THEN compare that to modern ROAD "performance" vehicles (not modern racing ones), the xB fairs VERY well. It is a sleeper in this regards.
As for the technology, . . .
The xB's performance is the result of Toyota's experience w/ racing related vehicles of the last 20-30 years. They have "perfected" the rather "industrial" architecture of the suspension to make it handle FAR better than it should. Most similar suspensions are rather sad in handling to OK. Toyota has made it rather remarkable.
My 90 Miata's suspension is FAR more "sophisticated" than the 09 xB's is, in regards to double wishbone, geometry, "classic" elements, et cetera. In short, the Miata's suspension of FAR more sophisticated than most realize, equal to a contemporary-vintage Porsche. As a result, the Miata is a "benchmark" for sports-car handling for the last 21 years and 3 generations.
By comparison, the xB2 gets handling that isn't far of (I DO have a 90 Miata and 09 xB), while using a far more "industrial" and simple suspension design. Toyota has RACED the same basic suspension on our xBs on Celicas, Corollas, MR2s, and related models, and even their WRC Corollas (abet modified for AWD), in many classes and organizations for many, many years (decades). All the while, perfecting it and making it FAR more than it should have been in theory.
Only Toyota could or would even bother to make a front-Macpherson struts/Rear I-Beam suspension into a "sports car" suspension that is comparable in performance to double-wishbone A-arms. Yet, that is what we have on our xBs.
Therefore, I would argue that the xB2s suspension IS the result of racing technology being utilized in a production vehicle. Otherwise, the handling would be more mediocre to "OK," rather than even having this discussion . . . or a fair number of members of this forum even OWNING xB2s (I would have gotten the black Mazda RX-8, Mini Clubman, or a Mazda 3 -maybe the Mazdaspeed one- the xB impressed me that much).