after having an r for 4 yrs and now havin had the z for about 1k miles I can say this.

z has a bigger tank range
fuelling is better but I never had much issues with the r
mpg is roughly the same if not a bit worse so far for me anyway on the z. average around 55mpg on the tenere but got bout 60mpg on the r. but I would cruise faster on the z so it's probably much of a muchness
vibrations on the z are pretty much gone but from top reaches of the revs
wind protection is miles better on the z. never had the issue of buffeting yet. at 6ft4 on the r with high hammy screen the wind hit me on the chin bar. on the z with stnandard screen the wind goes just over my lid.
handling is probably about the same if not a bit better for the z.

if you want to know more drop me a pm

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