I am almost there with the funds for a new slip on exhaust for my much beloved 1000RR

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It has only been a few weeks since I got it but am already very attached to it! I really like it. I serviced it last weekend (new oil, filter and water) and it must have used less than 200 ml in the 2000 km or so I have done on it since I got it

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I am already turning it into 'my' bike...which I like to do with all my cars/bikes by applying slight methodial modfications

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So far I have done:
- Removed white rim tape
- Added 1000RR fairing decals
- Honda brake socks
- Matte black metal tyre caps
- R&G black Radiator guard
- Yoshimura aluminium alloy engine sliders
Next on my list are:
- High quality slip on exhaust
- ASV Shorty levers (black with red setting knob)
- Power Commander
- 1000RR 2012 multi spoke wheel set
It will take some time to apply all of them, especially since I invested in some very good quality ride gear (priorities first) as I sold my last set a while back.
Now I would like your opinion on a decent slip on for my bike. I have talked to two local owners of 1000RR. Ones has a 2 Bros, the other an M4. They both sound nice. I like the looks and finish of the M4 better.
Both have added pc's on their bikes now but claimed that during the weeks they ran the bike without the pc, they did not experience any problems with running, fuelling apart from a few flap spots at low revs (below 3000rpm mainly) and some pops during engine brake from high revs...
I plan to add a pc at some stage but for monetary reasons I'm starting with the slip on..
I want:
- High qaulity finish.
- Decent price.
- Nice deep sound but not too loud.
- Some performance gains (mainly tractability but more top end power would also do nicely)even without pc.
What are my options? Is there a thread with photo, opinions etc?!
Thanks a lot in advance! feel free to post photos and opinions

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