I’d definitely recommend buying an M&S sports bra, I didn’t buy a macom and have only used my M&S bras, I bought a two pack of high support ones for £30 – they’re pretty unattractive but they’ve done a great job and always feel secure. Band wise I went for the same as I usually wear as I had a front zip up sports bra from matalan that I used initially for the first week or so until swelling reduced.
I had 325cc partials and bought my matalan zip up bra in a 34DD which was a little snug, I probably could have done with an E but after the first week I used the M&S bras and bought those in a 32D which have been absolutely fine, but I did buy a bigger size just incase (I kept the tags on and have taken back since)
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