I have recently changed my lights from MR16 to GU10. Took alot of research as I am not an electrician but my brother is. I bought these for the price and was pleasantly surprised with the quality as did my brother.
I have been looking for ages researching which light to buy, I wasn't keen on the look of the light when it was off (yellow squares) but you didn't notice them that much when they were in the ceiling. I was pleasantly surprised at the ward bright light that was given off, they are actually brighter than the halogen lights I had previously.