You may get initial leaks but a bit of carbon seals them up. I didn' and don't - are your dealers a bit crap? I've taken mine on and off too many times and never a problem - just last week to fit a new center stand!! (caution if you want to take yours off - pipe off but you could fit it properly at the same time)
For me after having taken mine of is to tighten the bolt behind the oil filter tight, leave the two clamps and the bolt by the footpeg loose warm up the pipe a bit then tighten the collars.
This makes it easy to install and more importantly I broke the lug on the pipe by the oil filter by not doing this!!*
I am really happy with it, light, good power although my alloy looks a bit bad after 3 years, I'm not a frequent cleaner, plus i can put on my legal can if its test time!!
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