'Haven't done a century yet (better do it soon after about 45 years of riding), but when I finally do, it will be alone. I find, on my 50-75 mile rides, that I really love being solo so I can take things in at my own pace. I also HATE trying to talk to other people while the wind is blowing in my face or I'm huffing up a hill, etc.

Yes, solo is the way to century.