M&S COLLECTION Tailored Single Breasted Waistcoat, £35 | Buy now from M&S
Finding that Goldilocks fit can take some trial and error, as lindyloo57 admits: "I like the look, took a lot of try-ons to find a good fit, as I've a DD bust. I found one in M&S - a black short linen mix one, I love it. I don't like the more formal ones on me."
Sunshine237 is a fan of the M&S offerings too, saying, "I have an M&S one. Had one last summer too, I like them for a proper summer with casual trousers. Sleeveless but not too clingy."
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Even the trend-wary are being won over, with Moveoverdarlin admitting, "I actually think they look really good. Very much a current trend so I wouldn't buy an expensive one. But I have a brunch coming up and I thought I might get one for that."
At the end of the day, the beauty of a waistcoat is its versatility as a lightweight summer layer, summed up perfectly by BigBurrata: