izso: regarding rear lower bar, imagine instead the same mount point was WELDED by the exact same piece of metal. will the torsion beam still flex? that's the same effect of the UR bar anyway. except its bolted on, but there's still no give/slack there, its effective as welding it.
On that article..its kinda contradicting with the statement you provided. In the article it states that stock torsion beam is designed not to be too stiff to make it fool proof. Adding an arb will reduce the flexing but too stiff a chasis will have the tendency to "lift" one side of the car up. Regarding the picture you had posted, what car is that and where did you get it? It seems to be a problem with the installation (my own opinion, of course). See the mounting point. The end of the bar is a round cylindrical like thing which should be bolted on horizontally and not vertically. But in this pic, it seems that the user installed the lower arm bar where it should be anti roll bar. And the bar shape looks flat, not round.
You seem to understand, but at the same time I'm not sure if you do.
The car is a Myvi
The product is UR Rear Strut Bar or Rear Lower Bar or whatever you call it.
1. What is the function of the rear lower bar? Stop flexing
2. What is the function of anti roll bar? Reduce roll to a certain extend by reducing flex, the thickness affects how much roll/flex is reduced. The ARB will still flex.
3. What is the function of torsion beam? To flex, as per the article.
3+2 = reduced roll, one is trying to flex, one reduces flex but it is still flexible, ARBs are very thin, for myvi usually 16mm or 19mm in diameter.
3+1 = one is trying to flex, one is trying to stop flex entirely, that rear lower bar WILL NOT flex. look at the thickness. its same gauge as the front strut bar. so the force from the torsion bar will fight with the lower arm bar, and see which one fails first. And guess who wins?
lucky the torsion bar worn, else its gonna be a very expensive bill.
so.. draw your own conclusion if the rear lower bar is rubbish or not.

I think its pretty clear, can't help if you catch no ball.
For UR, the stuff that are fundamentally same and R&D (robbed & duplicated) from Japanese counterparts like anti roll bar, strut tower bar works. its simple and straightforward. that being said I will be buying a UR strut tower bar for my mum's new car. Shit happens when they try to engineer their own crap.
and how does DSPORT with real Japanese engineers does it? You know how the rear dsport lower arm bar looks like? and how it mounts?
http://i26.photobucket.com/albums/c125/siawkk82/DSCN0662.jpg
they brace the chassis to reduce flexing on the chassis.
thats engineering.
so yeah, quit dreaming lah, you really do get what you pay for.
and its not expensive. the cost of buying a Cusco strut tower bar for the Myvi and the Lancer EVO for example, costs almost the same. You know why? Because the same amount of research & development and the same quality goes into it. want to be cheap don't play car, go play gran turismo on ps3. you're better off NOT modifying your car if you are going to install rubbish on to it (surbo, UR rear lower bar etc.)