Advice on LXmini variant - sealed box vs. folded transmission line

[ajs123]

I'm working on a variation of the LXmini, meant for tabletop or stand mount instead of the original straight pipe. SL included a wider/shorter pipe among the examples in his gallery. In addition, while he characterized the pipe as an infinite transmission line (meaning, at least in part, that what's reflected back to the woofer is insignificant), it seems clear that the real goals are (a) no significant reflection back, and (b) no significant radiation off of the walls.

I'm looking at two very similar approaches to a sealed box alternative. In either case, I anticipate building with layers of MDF, which makes it easy to make whatever cross-section is desired. In both cases, I've kept the border around the woofer the same as the original. SL states that there is some baffle diffraction in the original but it's unimportant since the effect would only be heard from the ceiling. It doesn't necessarily follow that added material around the woofer has no effect on the tweeter (comments on that welcomed), so I kept it unchanged.

The picture shows two examples, and I'd be grateful for comments on their relative merits:

1. An open box. Walls are 3/4" thick (detailing of the woofer mount not complete). It will need good dampening and fill.
2. The same box with a partial wall, forming a folded transmission line. In this instance, I've included a curved wall so that there's effectively a circular tube behind the woofer. A couple of inches from the bottom, the wall ends, forming a wide slot and vertical passage up the other side. I would still at least stuff with fill, and perhaps use some wall dampening as well. In addition to forming the folded transmission line, the wall adds a lot of bracing.

Is there merit to the folded transmission line approach? Or am I just introducing problems related to shaping of the passage and slot?

Thanks for any suggestions!
Alan