I think it's the equivalent of using de-railleur Bar-end shifters (the Hub-Bub bar end Rohloff Shifter) or traditional Down-tube shifter (Accessory Bar Rohloff shifter).
For derailleur, the bar-end shifters make more sense because they are in-line with your hand on the drops. That is, you don't need to reposition your hand so much to chamge gear, just nudge up/down. If you mount the Rohloff there you need to completlry re-orient your hand in order to twist the shifter.
Most importantly ask yourself how often you ride with your hands on the drops, for me it's mainly down steep hills (and then not always).
If you ride on the hoods, Derailleur STI is the best option and I wish Rohloff had this option....but they don't. The next best thing is the accessory bar because your hand naturally falls there. It's similar to the old downtube shifters but a bit nearer and only one to worry about.
If you ride on the bar tops, relaxed touring style, then it's simply the best option full-stop. The shifter is 6 inches from your hand.
All gear lever-postions/types are a compromise. STI is the best for making rapid progress in a heads-down position but the accessory bar is, in my opinion, a pretty good compromise for a touring bike IF you ride on the hoods or bar-tops a lot.
Just try it on your current bike, see which would be easier to reach, accessory bar or bar-ends. I personally wouldn't choose bar-end position now.
Good luck in your choice and, like I say, make sure SJSC leave enough room on stem for accessory bar or you'll scuff your knuckles.
