There isn’t a “best sports bra”. what one may think is good for them, may not be good for you. People rate the macoms, although i didn’t get on with it and felt like it squoshed me. My favorite by far is the Tescos High impact. Nice thick material and comfy. I had an M&S one that i found comfy, although it irratated my scars.
I got a “shock absorber” bra from Ebay and found that comfy, but felt it didn’t support me as much as the Tescos… trial and error babe.
Get a size bigger round your chest for if/when you swell. i didn’t have that problem and the size bigger was too big always, so just stuck with my regular size and got a couple of C,D’s and DD’s. Trouble is…each shop measures different. im a DD in Tesco, a C in marks and a D in asda!
i’d suggest you go get a few cheap ones a few days before you op…keep the recipt and take them back if no good. x