I had a iBG-star - was fine in winter - any higher than ~ 25deg ambient & it'd give continual errors. Took me about 14 goes to get a test result. My fingers were really sore.
I pulled it apart & well, as a professional electronics designer, I'm not impressed with what I saw inside. Hot-melt glue fixing a lithium-cell in? That's unprofessional! Not surprising it hardly works!
Went back to a Medisense. I'm been using an accuchek Aviva for over a year now. (I also worked with the engineer who designed the Aviva's production-test equipment, he's good & he said the Roche Designers were really good engineers too)
NOTE: these comments are more relevant if you're type-1, as we are doing a GREAT MANY (>5 a day) more tests than our type-2 friends!