I will say, I have been using the same Visc D18 for 2 years now. I can pack it in my suitcase. Now my suitcase can be used as a trailer but it does not have to be used that way.

I have had a Visc SL now for about 9 months.

Between the two bikes I have been able to ride in about 5 other cities taking a bike with me. Always checked the suitcase as normal (not over sized) baggage. The only damage I had was a bent chainwheel which I ended up replacing.

I think the evaluation of the Visc hinge with the compression member is very good. I find it to be very stable. I do pack both ends of the compression ring into padded "juice cans' actually just for extra protection and they have traveled fine.

Regarding extra Hinge Bracing I do have methods I have considered for that as well. It would be interesting to do a Gravel Trip with the big wheel/big tire Visc.

I wonder if you couldn't tighten that loose hinge, perhaps just with some Epoxy and Saran Wrap. Generally you can tighten the hinge clamp. My believe is that it is the clamp which is the weakest link in the chain. If your frame is loose, definitely you want to tighten it up. (Too tight though you might break a Hinge Clamp bolt).

I do believe the Visc has been an overlooked frame. It does have advantages in both the 20" and the 16" frame size. A small piece too, is the low step through is really nice when you have a lot of bags on the back. When packing to a suitcase it tends to pack a bit smaller than the MU frame as well. I am sure that is happen chance but valuable anyway when you want to travel with your bike.