I did some patching on my first Kobo. Maybe also on my second. I never really felt there was much benefit. I liked having the smaller bottom margin but that's a very minor thing to me. The Kobo's font features are sort of nice when they work but they often don't work with side loaded books and in recent years I rarely even try them anymore.
To me the advantage of the Kobo is it's small size and light weight. Mine are Kobo Auras and I like them. My Kindles are more reliable and the features I really care about work well. Also I get the Kindles with 3G and that means I can access Wikipedia when I'm away from Wifi. I like looking up new concepts and new contexts for old concepts as I read and I miss not being able to do that if I take the Kobo with me.
Recently I'm reading more on my phone when I'm away from Wifi so all of this becomes a bit less important.
The fact is that if I could have only one ereader I'd prefer a Kindle but I'd be happy enough if it was a Kobo. However I'm very glad I'm not limited to one ereader.
Barry