Seen HERE

I have one and have slightly modified a Swedish slip-over "stove" to mate with it.  See ETA remarks above in my relevant posts.

The ultimate goal is to slightly and carefully bend/reconfigure the upper edges/perimeter of the Swedish stove to accept the larger German top cup and allow the whole thing to fully slip inside the Swedish stove.  Likely some additional cutting required on side slots of stove, but most of this will be careful bending of the upper perimeter of the Swedish stove.   Will advise.

For those not willing to tinker with such things, the abovementioned stainless-steel PFM40 Pathfinder Cookset is a fine article.

Like all PF Items I've seen/tested, the stainless steel in PF items not attracting a magnet indicates the metal is "food-grade".

Been tempted to get a few to keep in the boats and snogo.

Also a Billy pot in each boat and even one of those twig stoves.

The PFM40 stainless steel cook set is likely the best way to go nowadays, as far as a "large" multi-fuel cook set goes; likely OK for max of two careful users. Some folks distrust Foreign-made Aluminum items, and I can see their point.  PF items, as far as I can see with items bought from them, are "food-grade" stainless steel.  For the most part, if stainless steel is NOT magnetic, it's "Food-grade".

The included bottom of the Swedish/Pathfinder stove allows user to use an alcohol stove, fuel tabs, and even twigs to heat the contents of the cooking vessels.  Some folks have used extremely low-profile butane burners.  BTDT.  As always, do your testing in "benign" environments.

Some folks have mentioned using the aluminum stove from the Swedish cook set to replace its heavier stainless-steel counterpart on the PFM40 for weight savings.  

Shop around for the PF item; and be patient.  Sales come and go.  Shop around for the Swedish cook set base, if the cost/benefit of price/weight savings appeals.

Lids for most vessels of this type of cook set can be bought or hand made.  See YouTube links above for making hand-made lids or buying them from nice Brit vendors (also linked above) who are forced to deal with brutal shipping prices. Personally, I very much like lids for cooking vessels, as such lids reduce cooking time/fuel usage, as well as preventing ingress of crud into cooking vessel.  YMMV.

What's the appeal of these kits? I keep looking at them but it just doesn't seem like an improvement over many of the more modern set ups available.

I use a nesting cup with lidded pot. My stove, extra cup, and gas canister all fit in perfectly. I'm not saying this suggesting one is better than the other, just trying to get some perspective on what advantage the German style kit has besides looking way cooler.

I got that exact one. Bought it many many years ago, works just like it should. The handle that is supposta fold down and hold everything together doesn't do that. I had to put a small bungee around it so it wouldn't fall apart in my bag.

There's nothing particularly special about these kits, except the one linked has 3 vessels instead of the usual two.  This allows a savvy user to cook/heat three items simultaneously instead of two.  The "magic" comes in when the Swedish slip-over stove is used.  The stove allows multiple forms of heat to be used, including twigs, fuel tabs, alcohol burners, and even low-profile butane/propane burners.   It's a good windscreen, too.

Obviously, this type of item is not for the typical ultralight camper, but these items may serve for other applications, and other users.  The rather large "main" cook pot may be useful for winter campers who require large pots to melt snow for drinking/cooking water.

The "three-piece" stove will allow the larger Mil-type stove to be stored in the lower pot, and appropriately size(d) fuel bottle(s) to be stored in the intermediate vessel, possibly with various fuel ignition devices.  Stove will likely need some additional material wrapped around it (suggest some 3-M green scrubbies) to prevent rattles.   If using the above-suggested BAE/Eclipse Gas mask bag, there is room for eating utensils, optional vessel lid(s) and an additional appropriately sized alcohol fuel bottle within the GM carrier.

A lot of folks bought this style of kit back when they were usually very inexpensive.  Prices have risen, so most of them are not as cheap as they once were.  Nowadays, other cook sets that you (and I) own might be preferable for some uses.

However, if one already has one of these kits, or can get one for cheap, then modding it to make the most of it might make sense.

@CTYC313

Some "Context" and hopefully useful content added.

Chinese cookware?

IDK where these cooksets come from.  I understand reluctance of some folks to use any sort of aluminum, especially Chi-Com aluminum.

I'd trust some aluminum, such as offered by Trangia.

I understand your concerns, hence my suggesting the Pathfinder cook set linked above, which is made of food-grade stainless steel.

Others will need to determine if unspecified-origin aluminum meets their needs.

Some folks will go the Titanium route.

Fortunately, we have options.

Looks a lot like the East German sets that were available in the early 90s.