If you seriously think that flat keys are better, you're seriously mistaken. The Logitech K800 which I have, is far, far, far, far worse for typing than any other keyboard I have.
And yes, you're correct, you need the Logitech Unifying receiver and you won't have to worry about it, but the battery life is also quite long, I gave it to my sister and she only recharged it once in an entire month.
But none of that would make me choose it over a CM Quick Fire Rapid with Cherry MX Blues if it's programming you want.
flat is bad for your hands.
Get an ergodox if you're serious about coding..
Actually, I read that a lifted keyboard is bad for your hands.
Might not be true, but it makes sense.
I call bull**** on that one.