Thanks everyone for all the really good input. I've come to terms with the realities of not having a spare tire in the GLC 350e. I plan to get a tire repair kit (sealant/compressor) as well as carry a plug kit. When the run flats that come on the car wear out I'll replace them with regular tires. Incidentally in investigating tire repair kits it looks like the $340 one that MB sells is rebranded ResQ kit from a German company called Airman. I can't say with certainty if it's the exact product but it looks to be and can be had on Amazon for $48 and they have some higher end kits as well.
As for tire wear due to the staggered tires, I'm hoping, maybe naively, that it won't be as bad as my W212. If it is then I'll buy cheap tires like these Front / Rear that I've been running for years on my e-350 and have worked out great.

My dealer just got a GLC 350e in yesterday so I'll test drive it Monday or Tuesday and assuming all is good I'll get one configured to my liking on order for Late November / Early December delivery.

 

Just for the record I didn't get a single reply in the GLC forum. As you say different experiences there and I think different type of enthusiasts too. I definitely got the kind and quality of replies I was hoping for here and very much appreciated.

 

yeah, our experiences with w212 E really aren't applicable to your GLC's...

 

EDIT: It appears the difference between the two products is the Pro+ has a built in LED light to assist using it in the dark.

Not sure what the difference is between the ResQ and ResQ Pro+, but for the extra $4 I would get the Pro+ (just for bragging rights). https://a.co/d/3gf4Xe7

I do believe AirMan is the OE manufacturer for Mercedes, just like CTEK is the OE for the Mercedes battery trickle charger.

 

I just thought to include this Consumer Reports review about tire repair kits.

 

Apparently the ResQ Pro+ is the favorite.

 

It wouldn't hurt to carry a tire patch kit too. They are pretty cheap. I went overboard with my existing spare because I have a tire patch kit and a resQ just so I have different options for whatever scenario comes my way.

 

Carrying a full insertion plug type patch kit is my plan too and in fact would be my first choice if I am able to find the puncture. I’ve used and seen them for three decades with my jeeping activities and they work great. Depending where the puncture is located they can be a pretty permanent fix although that might not be a good practice. I’m just pointing out the effectiveness of them.

 

And effective they are...

 

The screw-in plugs shown in #20 above are interesting. One of the consequences of the full insertion plugs is that you can damage the tire carcass and belts installing them, first with the rasp and then with the plug tool. The screw plugs would seem to fill the hole in only the rubber tread and stop/slow the leak until you can get to a tire shop and have a patch installed on the inside.

So far, we've got tire patches, engine oil and spark plugs all discussed in a thread that started as "staggered tires". Anyone want to talk about windshield chips? (lol)

 

Mostly covered by other posters, but I'll add my 0.02:
Yeah GLC different than a W212.
If the rears are wearing FASTER than the fronts, what are your options? Are you going to put narrower tires on the rear? IDTS.
I have had aftermarket staggered on my ride for several years with no issues.
Allegedly, EVs eat thru tires like a 6 y.o. thru chocolate :-) You may wish to study the hybrid system you are acquiring to determine engagement level and torque throughput. Also, MB may have hidden settings to adjust that throughput to your liking.
Another option maybe to change the tire compound of whichever pair wears first depending upon driving conditions. GLWP.

 

re 12VDC compressors, I really like the Viair ones, like the 88P. The 88p has battery clips rather than a cigar lighter plug, and they recommend running the engine while inflating as the higher voltage will speed things up. It can be run for like 30 minutes straight before it needs a cool down, and in that time can inflate 4 pickup truck sized tires from fairly flat to operational pressure.

 

I've actually used both the string-type plugs and the screw in type, and both seem to hold air perfectly. If the damage is in the tread and I can plug the hole, I leave it like that. There has only been one time when the damage was unrepairable, and I took the tire into the Mercedes dealer (where I had purchased the tires). They replaced the tire, no questions.

 

Here's another good video.

 

These are superb ...best portable/emergency compressor I've ever used (and I have had bad ones in the past)! Had mine for many years now, used it twice on the road (big Suburban tire once), and just recently in the garage when my home compressor died. These Viair compressors are fast! But they do get hot so caution with handling it after it has inflated a tire. Fwiw, mine has the standard cig-lighter socket, but I also have the battery clips adaptor that I stuff in the bag which allows me to power from battery terminals if need be.

Edward