I have a Cygolite Hotshot 100 that I purchased from Amazon almost two months ago. It's now showing signs of failure as evident on the last two rides. It will run approx.10 minutes on daylight mode then shuts down inexplicably. I've charged it at home and the light blinks as it should but turns solid after only 10 minutes signifying a full charge. Go figure. Fortunately, I’m still eligible to return it by May 31 but now am now unsure if I should submit a claim to replace it or request a full refund.