I spectated/bag held/coat held for family members yesterday as they did a half marathon, so I had a lot of waiting and standing around to do. I wore my new coat that I bought for a whim on ebay, one of those Regatta versions of a 'dry robe coat', which runs oversized. I looked hilarious wearing it but it was fantastic at keeping me warm from 8am-12pm in 4-6 Degree weather. It's too comical to wear to work but it shall be my weekend walking coat. I felt so smug (and snug) and warm

This time last week I was thinking of sending it back because I thought oh this won't work, but my impulsive thoughts won and teared off the tag and said jusssssst keeeeeeep itttt

I do tend to go for about a 2 hour walk most weekends so I suppose it will get used.
And here was me a couple of years ago mocking dryrobe wearers

What made me search ebay recently was when I was on one of my walks I saw lots of dogwalkers looking very snug and warm in Regatta or dryrobe or other brand of the same type, whilst I was still feeling chilly in my jacket length fleece and waistcoat. Having something down to my knees is a game changer. That plus fleece lined leggings.
One thing I will say though is the Regatta version is a bit loud noise wise, but that might be because it is new and it is waterproof. But then again some of my other Berghaus/Trespass jackets are too.
Now I have reached mid 30s and with mild asthma I'd rather look like a snug gnome and cover my body with warmth than underdress and get ill.
TLDR: those long dryrobe style coats are actually quite fun to wear on cold days.