I can't speak for the Galaxy Note, but when I replaced the battery on my iPhone, it took me perhaps twenty minutes with minimal tools (screwdrivers, suction cup, plastic "spudger" -- all supplied with the battery) and no prior experience. Could probably do it in half the time with practice.
When I took out my Samsung Note 2 battery it took me perhaps ten seconds with no practice either. Twenty minutes for replacing a component they know is going to wear out the quickest of all components is long and a dick move by the company.
To give some perspective, this was for a phone that was around 4 years old, and which had been sitting in a box fully discharged for a while, destroying the original battery.
Twenty minutes of work over four years is not a big deal.
