We've been living with a defective sprayer for the last month, maybe two months now, but have been a bit hesitant to purchase another one. The push bottom was stuck on the sprayer and wouldn't swap over to the sink and it's been a huge pain to do anything at the sink. During these last few months we had our contractor friend look at it while he was working on a few other items and after a few wackes on the side of the sink the button released, however, within a day or two it was stuck again.
I found this video on How to install a kitchen sprayer very helpful and less intimidating then some other ones I watched. Although, it was still wasn't as easy as they made it since I had so many obstructions to work around under my sink. We have a garbage disposal and our hot water comes out the back of the cabinet and then connects to another tube to our hot water so it was a bit of a hassle to get around them since the blue tube wasn't budging.
After about 30 minutes I successful installed my Christmas sprayer and it looks much nicer then our generic sprayer and we're looking forward to using our faucet and water filter again.