The 15" version is enjoying some good success in small sealed apps. Yeah, the 18" is a sweet offering. What's fascinating is the manner in which the former appears to be connected a mini-cone, subsequently connected to the curved cone. I'm not familiar with such an approach.
Here's the image showing what I'm referring to. Doesn't necessarily mean anything, merely an observation I find interesting.
Not yet, however, I did just finish the extension to my house for the home theater which includes space at both ends for IB. Now that I am retired I have time to finally build it out once I finish the wife's kitchen remodel. I am now thinking an SBA might be the way to go with absorption at the opposing end.
Right now I'm in the process of building a couple of sealed subs using these drivers plus the flat packs from PE. Neat that I can use them in IBs later. Just got to remember to lay some kind of weather stripping between the driver and the Duratex coated box.
Recently tried pulling out some other drivers from sealed boxes that I had built early, directly mounting the drivers into the boxes while the Duratex was not 100% cured. was going to play around with different amounts of poly fill. They didn't even budge, so I stopped while I was ahead.
Just a quick comment that this driver is pretty amazing. I use one in a 9 CuFt. sealed box, driven by a Crown XLS 2500 (2,400 watts) as a way to smooth out room modes to the IB I have at the front center of the room. The sealed 18 is at the rear center, and when delay and EQ are applied, it blends very nicely with the IB.
I still dream of buying two of these and replacing the sealed box with another 'outie' IB at the rear, as it would share the same crawlspace under the home theater with the front IB (a 4x15" outie manifold). The symmetry of front + rear IB's would be nice. But it all works so well now, I'm happy.