FZ for self and pillion comfort.
R15 for everything else.
I am owning an R15 for the last three years and have covered around 50000 kms till now and out of that about 30000 has been covered with my girl friend as pillion. I love to visit places and the most difficult till now was my trip to Bhutan as roads are extremes on the way. Yes I had my lady as pillion.
Having used this vehicle till now I have faced no severe challenges while travelling other than unwanted attention and yes I never had to spend anything on the engine yet. Total maintenance I spent till now should not even cross the 35k mark in three years.
The only challenge I faced in an R15 would be the lights. Hence I upgraded the battery from 2.5 amp to 9 amp (1750/-), altered the stator from three phase star configuration to three phase delta configuration (500/-) and replaced the RR unit with APE three phase RR unit (1700/-). With that you can happily run 60/55w in both headlights without any issue. I am currently on 50w 4300K HID and I am happy.
Note: R15 delivers better fuel efficiency FYI
. I have a free flowing exhaust (Daytona Dagrex) since my bike was about 8000 kms on odometer and I have always got kmpl figures above 40 with pillion. At times at early 50s too. I am not an exception many of my friends get similar figures too but none till now I heard of gets more than 40 kmpl on FZ. Mentioned just in case that is something you want to consider.
PS: You might as well consider the Suzuki Gixxer 150. I have ridden that back to back with FZ v2 and the performance is far better in that. Didn't ride the faired Gixxer 150 yet but saw it in flesh and it looks super, also the riding posture is much relaxed.