So far, I've added a large CalSci windscreen, which I'm currently sending back for a replacement. It arrived warped badly. I installed it before I noticed it. After talking with them, they advised me to ride with it for a bit and make sure the size fits me well so they could swap sizes if needed all in one shot. Good service I'd say. The windscreen works well too, but isn't exactly sexy.
Just the other day, I added Touratech engine guards which installed easy and look robust. I also installed the Garmin Montana locking mount in place of the factory gps mount. Simple install and seems like it'll work well. However, it's a bit larger and hangs a bit lower than the factory mount so covers about half of the tach. I have plans to move it higher with a adapter if I find it bothers me too much. However, I've gotten pretty comfortable with the bike now tha I don't exactly have to stare at the tach either so I may just run it as is. We will see if it bothers me long term.
'13 BMW 1200 GSW
'05 Honda ST1300