Tombiowami and I saw one the last time we dove the local quarry. I can't remember what color it was (Tombiowami?), but it looked ok. I read the review in Sport Diver and saw the Immersed ad too...
Tombiowami is right though...if you think about being horizontal in your Halcyon rig and reaching back with your left hand to actuate the dump valve...easy, right? Well, the DO dump valve is on the OUTSIDE of the wing...like where your Halcyon is, but on the exact other side of the wing (facing away from your body). Not sure how the hell you are going to reach that...I guess your buddy will have to vent your wing when he/she sees you heading for the surface at a rapid pace.
Alternatively, you could tie a spool off onto the air dump and give the other end to your buddy...then he could dump for you like he was shooting a bag...
Or...wait...you could rub your back against the wreck until it catches on something and dumps all the gas out of your wing and then deal with the entanglement...like it says, it is a "tech" BC so you should be able to handle a little entanglement, right?
I don't think the pioneer is headed for ebay just yet...
wait...another idea, what about tying some line off to the dump valve and then routing it over your left shoulder to your front left D-ring and then dumping from there...that might work, although that creates another piece of convolution that could lead to more entanglements...
DO, if you are out there why not send me one to test?
Of course, I would need a set of doubles to test it properly...