Many times, I agree with Atif but sometimes I want a separate pot/mug.
I have and like this set. I’d have to double check but I think both of these fit over my 95mm Toaks 550. I know the larger one does for sure and can function as a lid for packing and boiling.

I don’t think those are made any more but you can probably find them. The silicone bands are thick and wide (heavyish) and their newer versions have titanium wire handles which probably make more sense.
You mentioned faster boil times using the 115mm variant. I am not a stove wizard but I suspect the 20mm is not going to show a significant decrease in boil time or fuel consumption. Personally I would buy the diameter that packs best and/or what you enjoy using.
The 400ml short/wide cup is nice.
The MLD mug is wonderful. I really like drinking out of this one not made any more.
I also like drinking from a Whole Foods gelato container (similar to a talenti container but lighter and heatproof in HDPE or maybe polypropylene). This slides right into my Toaks 550 and has a lid that seals well so it has cold soaking potential.
I’m happy to measure/weigh any of these if you want.