I have had two aprilia Tuonos now and still have one, they have been flawless except some tank issues which were fixed under warranty.
The tuonos are almost always my go to bike for general riding, that could be curvy back roads, highway, or going into town and traffic. The engine is just awesome on the v4 i like the v twin one also. I have ridden the BMW it just dont like it, and i am a fan of the flat twin bmws but the inline 4 is just not for me, i dont like the way it feels. But i also grew up ridding twins so that may be part of if.
I have not ridden the ebr yet, but i am seriously considering getting one now. I have been a long time buell fan and have had several and would love to support Buell now that they are open again. Of course like everyone has mentioned there is the dealer network problem but for me it does not really matter anyway as i work on my own bikes. The only thing that could be a problem is if there was a major recall or warranty repair. But i have personally not heard anything like this.
In past years this would have been a easier decision with EU bikes costing more but they have come down, so it really comes down to your riding style and what you like. All 3 have very different engine feels and that makes a big difference.