I think you might benefit from trying to figure out what the advantage of the octo/inflator is. One fewer hose? That's not really an advantage in the water. It just "seems like it" in a dive shop showroom. The big disadvantages are: 1) you need a longer-than-necessary corrugated BC hose, which adds clutter to your chest area. 2) your inflator, which you use very frequently BTW, is now bigger and more complicated than it needs to be. More clutter and potential confusion in inflating/deflating your wing. Don't forget, someone else might have to do that for you in an emergency. 3) If you have a problem with the regulator or BC on a trip, you can't simply switch to another because the LP inflator hose has a proprietary connector. 4) Imagine a leak at either the inflator mechanism OR the alternate 2nd stage. With one of these contraptions, you lose both if you have to disconnect due to a problem in either. Leaky inflators are not uncommon. With a normal inflator, that just means you have to orally inflate. With an octo/inflator, it means you lose your alternate 2nd stage or continue the dive with a leaking inflator. 5) Air sharing is complicated by the fact that you now have to remove your 2nd stage in order to fully vent your wing in some positions.
They don't tell you this stuff at the dive shop while they're crowing about one less hose......
Now, for the upside that you mentioned, you do know where it is, but that's also true with an alternate on a short hose with a bungee necklace. In fact, you can even get it hands free with a little practice. It's a much better configuration. The tech guys really have this one figured out.
Reconsider the octo/inflator, you'll be happier without it.
