Ok, somewhat out of topic. But when I read that OX9 pedal attachment, I just went ok…so what have they've been smokin?
What's the point of releasing anything, that you anyway have to buy A THIRD external footswitch anyway to it? If they're going to release anything, make it with all three footswtiches on there from the start on! Where's their heads at?! That was my wish from the start on, that any delay pedal, or a pedal like the H9 needs to have 5 switches to cover it all. And then they release one with two… jeez…
YES, Wish they release a OX9 "cradle" with all three buttons on there for a start. Don't give me the yadayadas about not enough space, because there is. I can understand the expression pedal bit though. That one should be the only one that should be connected to the external jack for the OX9/H9. And on top of this, with that "cradle" stuck on the H9 one can't seem to put velcro strips underneath it because you must leave the fastening to the H9. So it can't be stuck on a pedalboard without some really unwieldy and cumbersome workaround.
Fix that! 
It really is a matter of room on the OX9. If you look at the folks who made these accessories, they started with our Factor pedals and on that model there is a third button, because it's wide enough. Not sure how big your feet are, but mine are huge and a third switch across would be useful only if I cut my foot in half. It's also nice to be able to put the tap tempo (or whatever you assign the switch to) in a different location on your board. Go to Radio Shack and for about $5 you can easily make your own third switch. You don't have to purchase the Tesla, even though it's very well made.
It was super easy to remove the old velcro from the bottom of my H9, put the OX9 on and then put velcro on the bottom of the OX9. I'm not sure how that's a problem, but perhaps I'm not understanding what you meant.
There are tons of aux switches out there on the market. I've easily tried about half a dozen, including the OX9, and they all have their plusses and minuses. The major plus of the OX9 is that it saves a lot of space and weight, which for me, is a big deal. If it's not for you, I recommend the Switch-3 from TC. It's built like a tank and works very well, but is large and heavy. To each their own.
