I never use the 11-tooth cog on my typical rides, but I like having it as the top gear. It pushes the 13 and 14 closer to the middle of the cassette, and I like using those in combination with the small chain ring to avoid front shifting when I know I'll need a lower gear soon. I would be perfectly fine if the 11 and 12 were replaced with spacers, but having a 13-28 10-speed cassette would not work for me.