The distribution of motors seen on the water is regional, some locations see a much higher number of certain brands.
As I said before, the Mercs outnumbered the Evinrudes of those years around here by 10:1, as the years go back further that ratio is reversed. Now it's 10:1 Yamahas over all other brands combined.
These are used for trolling, running all day long, day after day, the guides around here put mega hours on their Kickers, the Mercs held up fine, my 97' still works perfect. The difference between the Merc and Evinrude is more about feel and comfort while running the motor, not anything to do with reliability, my somewhat older Evinrude 9.9 still runs fine too.
The Evinrude is a much older, tried and true design that will last along time, the Merc is a much newer design and runs quieter and smoother, plus the shift in the handle works very well for how the motors get used around here. Parts for each are easy to find, so that's not really an issue.
What I will say is that both motors will serve the purpose, I will also add that I haven't used my Evinrude since the first time I put the Merc on the boat, I like it that much better. The Evinrude is now used as a back up motor if the Merc is out of service, that hasn't ever happened though. So now it's used as a loaner motor for friends that need a kicker, or on one of my boats that is loaned to someone.