I normally get my undies from M&S but have noticed the past few bras I've bought have been crap. When I wash them the outer fabric seems to shrink a bit so the inner layer can't lay flat and ends up puckering around the edge of the cup meaning I can only wear them with baggy tops (which is pretty much only jumpers in winter). I don't wash much over 40 degrees and nothing else seems to shrink.
I watched TV prog where Gok Wan visited a factory in China that made bras. The same production line made for M&S and George, that's not to say the materials or designs were the same though. I bought George for years but then I 'treated' myself to a couple of M&S ones, the fit was much better TBH they have worn better too. In an ideal world you should really handwash bras especially wired ones and hang to dry. Fabric conditioner and tumble drying cause the early death of elastic/lycra.
Most washing machines have a handwash setting these days but also a thing I have found works well is don't use fabric conditioner as it ruins the elastic in them
I remember from watching that Gok Wan programme where he visited China that they are all made on the same production lines so I'd hi me hence to Asda and stock up.
Life is too short to hand-wash bras.
EB your not alone, i have to wash my clothes at 60 to kill bugs and germs because of little fs germ catching and the bras dont like it! i find manipulating the fabric whilst it drys helps the puckering