Congrats on the new ride. Good choice, I have the same

Switching out the exhaust does require to remap. Your local KTM dealer can load the akra map. Any exhaust will sound good on it,its a twin I have the FMF Apex, they sound awsome. The Leos are a popular choice in europe you should support your local economy and keep your cash in CA haha I've posted pics in the gallery of the FMF. If you want I can take a few more angles for you.