[folivier]

I had the same issue as Richard. On probably half of the fixtures I had to pop off the back cover and hold the clips while I inserted the leds. I usually try to find someone on ebay that is in the USA in case I have to return them. Much simpler than trying to return something to China.
The leds I bought have 9 leds/fixture and I find they are the same brightness as the halogens. I used the light meter on my camera to compare the brightness.