After only four days (from which a weekend!) my 20 feet (6 meter) of 1/2" blue Danger Den UV tubing arrived:
I have to say I'm very pleased with it so far (although I didn't install it yet).
These are the different 1/2" tubings I have (and used):

From upper to lower:
- 1/16" wall silicone tubing (bought locally)
- 1/8" wall DD blue UV tubing (=Primoflex from Primochill)
- 1/8" wall R-3603 Tygon tubing (Danger Den)
- 1/16" wall R-3603 Tygon tubing (BeCooling)
The DD UV tubing is as soft as the 1/16" wall Tygon (the 1/8 wall Tygon is less soft), but less than the 1/16" silicone tubing.
To the touch is has a feeling somewhere between Tygon and silicone tubing.
Concerning kinking it's on par with the 1/8" Tygon, which means very good.
Now I have to see how it will react in time...
CD