BMW R1150RS Exhaust - What, Are You Nuts?

I'm looking to upgrade the exhaust (retaining the header pipes) on my 04 RS. Why? Well firstly it has a CAT the size of a Corsicana Bakery cake tin that sits directly under the engine and makes for toasty times year round. Secondly it has a pipe the size of a SAM launcher and thirdly, the whole shebang weighs more than the rest of the bike put together (exaggerate? moi?).

Now for those that aren't in the know, the 1150RS started BMW's now tried and thoroughly tested "nothing else will fit so buy from us or suck it up buttercup" policy. In other words, it's not just pull off the old can and slip a new one on for instant weight loss & HP gains.

So my plan is to have my local muffler shop make an S-bend pipe that will connect the headers directly to an aftermarket pipe. I'll tap in the O2 sensor to this pipe and the CAT will be no more. Whereupon I can connect a nice, light, slip-on exhaust of my own choosing.

My questions are (and goodness, I apologize this got long...), am I missing something dire, horrible or potentially fatal to my bike here? And, any recommendations on an exhaust system? I thought a unit designed for the same year GS or R models would offer the right balance since it's all the same engine. Akrapovic sure looks nice.

Thoughts & guidance would be appreciated here. Thanks in advance for any & all.

A muffler shop is almost certainly going to make the adapter pipe out of mild steel. Get it chromed or rust will show up within hours. High temperature paint will be a temporary fix at best.

Good advice - apparently they can't bend stainless (needs a mandrel).

Have the whole thing ceramic coated.

Just in case anyone was wondering, could an exhaust system be as bad as he says, I give you Exhibit A.

+1 on ceramic coating.

http://swaintech.com

Not affiliated. I did my research and found them to be the best-IMHO. Did my F800GS and am impressed.