Although I do see ClieOS opinion on Sleek being 2 steps behind, I guess I fail to see the correlation with IEM advancement. I mean BA technology is just reworked old hearing aid technology and dynamics are what they are. Sure, you can tweak the sound to make the sound specific, but I don't see that as advancement. Sure, you can add exotic materials like carbon fiber, titanium .etc, but in the end, it just an IEM that will sound like the way it's manufactured to be. Other than Phonak, I believe Sleek is the only one with changeable filters, but Sleek also has the wireless technology at a fairly consume level price. If anything, when Sleek came out, they were ahead of the game. Fast forward now, sure you have more drivers, but like Phonak with the PFE232, it chose two, but very unlike Phonak, it appears that Sleek wisely priced it within respectable range. From what I read about the PFE232, with its dual driver it appears to be proof that you don't need more drivers for really good sound. Also, like other IEM names in the playing field, Sleek does have its own line of custom IEM.
You feel it that way because you are in the game (of chasing IEM) much like most of us here. I won't exclude myself out of the game but there is one thing I think I have the advantage of - that is I have been collecting IEM since late 2005 and have observed how the market, as well as how we value IEM change with time. Just about two~three years ago, there is no such thing as $200 top-tier (or if you like, lower top-tier / upper mid-tier), $500 never get you beyond an entry level dual driver custom and a 4 drivers custom that cost almost $1500 was the king of the hill. But things sure have changed now. There is no Westone 4, SE535, K2 SP, EX1000, PFE232, etc on the market when SA7 was announced, and now they have surpassed what we used to believe was the best sound quality a few years ago. Not to mention now we also have more than a handful of sub-$200 IEM that are really excellent sounding on their own right - these are all competitions that SA7 has to face because of its delay, because customer who were willing to pay $400 for SA7 1.5 years ago probably already used that money for something that is half the price yet capable of competing closely to those that cost double. The game isn't the same when SA7 was announced, and that is the advancement I am talking about, not just purely on the tech side but also the value side of the IEM market. This is why I has said, "Time is going against Sleek Audio on this".
I am wholeheartedly hope that SA7 will be as good, if not better than what I think it will be. But the reality is, Sleek Audio might find itself in an unfamiliar place again when they come back to the universal IEM market because how much the environment has changed.