For me personally I think tethered. The cable is right there when you need it, no messing around.
It's raining, you have one less socket to try and attach to etc.
I totally agree with
@defeatedbythecat .
Yeah - The debate over tethered vs untethered wall boxes is a totally personal preference thing really for me ?

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It's very much a "Roundabouts & Swings" topic.
Only speaking for myself here, I went for a tethered unit and purchased a type 2 cable to keep permanently in the boot of the car.
The type 2 cable is dedicated for public charging use ONLY and never leaves the boot, unless for charging of course !.
I know that solution can be seen as more expensive option, because in effect buying the charging lead twice in a way, if thats makes sense ??.
But this maybe worth considering before you make your choice.
Okay, you have favoured a untethered wall box ( cheaper option ) which you are using on a daily basis and are very happy with your purchase.
Then one morning, you are about to make a long trip and you are running a bit late ( as we do ).
You unlock the car, unplug the lead, jump into the car and set off on your long trip.
After driving about 100 miles ( ish ) you decide to take a well earned toilet break and something to eat and a drink.
While there, you decide to carry out a quick charge at the same time.
You pull up to the 7 kw public post and then ( hard face palm ).
Where is your charging cable, still plugged into your home wall box 100 miles away !.
One good enough reason to go tethered, right there and then !.
Either go for a tethered wall box at home and purchase a dedicated type 2 lead that lives in your boot permanently.
Or go untethered and buy a second ( more expense ) type 2 cable to live the boot.
You can't get it wrong with a tethered wall box, because the clue is in the name.
It's TETHERED - as the cable is permanently attached / fixed to the wall box unit.
Having one untethered cable means you are constantly taking it in and out of the boot in ALL weathers in order to charge.
If you go tethered cable and the lead becomes damaged in some way, it can be replaced in about 30 minutes, so not the end of the world really.
A untethered cable can get damaged as well don't forget !.
It's each to his / her own on this subject, you pay's your money and takes your choice, at the end of the day.
Very similar to these two subjects :-
"Do I purchase a spare wheel kit, or do I rely on the useless, but supplied inflation fluid ?".
Combined with :- "Is carrying a small 12 volt battery booster pack a good idea, do you think ?".
I think you already know the answers to these two questions

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Preparation is the key to success !.