So, I have actually gotten to use both of these, but not for very long and with very little field experience.
When I was doing my DSC1 (and practice for it), the keeper lent me his set of viper-flex styx. They felt good, light in the hand (but I wasn't exactly travelling far with them...). Although the keeper did point out to me that in windy conditions they whistle - although this is because he'd lost the supplied cover for the adjustment holes.
Fast forward 3 months, and whilst out with a stalking guide, I got to use his Blaser sticks. Weight wise, I felt they were comparable to the viper-flex sticks. I personally much prefered the traverse on the Blaser sticks in comparison to the viper-flex front bar.
Ultimately, I wasn't keen to do a DIY set, and am a bit of a tackle tart (buy once and all that?

) so didn't fancy trying the Bushwear/StableStick options - as I'd read of folk bending them out of shape by sitting on them etc.
Local shop to me has the Viper-flexs listed at £195 (if I remember correctly), but then found out I could get a set of the Blasers whilst on holiday in Europe for £240 (I also had something in reserve from Santa) - and bringing them back was just a case of packing everything into the missus' suitcase then the sticks get checked in as sporting equipment. Still a bit of a spend, especially compared to the B&Q option, but in my
very limited experience (3 days stalking and handful of range sessions), I'm happy with my purchase and felt like anything else would have been something I'd gotten in the interim before plushing for the Blasers.