Dominator HP8 slip on for the KTM Dukes -- will fit 790/890/890r. Simplest slip on install I've ever done. Literally minutes. Much lighter than stock, nice carbon end tip, and a nice rumble with the cat retained. Would really bark on a catless system. $299 USD on Ebay: 890 Duke / Duke R 2020 - 2022 Exhaust Silencer Muffler HP8 DOMINATOR | eBay.
Check out my install and running video here -- I'm not a pro videographer, but as I said, I was surprised at how quick and simple it all came together -- very well built to exacting tolerances.
Photos are the exhaust on my actual bike. Really sounds great on the throttle. Can confirm it clears the turn signal on the j-tech tail tidy-- should be fine for others as well -- don't melt your turn signals! Also no melted boots -- really well thought out. Only ridden for about 200km. We'll have to sort shipping. I'm in Canada but never any issues shipping to the 'states! My European friends should order direct from Dominator in EU. I don't have the DB killer, but one can be ordered from Dominator for ~$20 USD.