Confused. #kernel #nexus5

I've been using the Nexus 5 for over a month now and find the device pretty amazing. Although the device has its own share of minute bugs, it still overcompensates for it in other places. Praises aside, i wanted to ask if flashing kernels can effect the phone in a bad way. I had flashed many roms in my previously owned SGN2 but never any kernels.

But now on XDA, Franco kernel for Nexus 5 has gained about 600,000 views in a short time. This has led me to think that flashing kernels might be a good idea (considering such a vast majority of people do it) . So can anyone point out the negatives and positives if there are any...

Much Appreciated.