All non-breatheable outerwear materials are boil-in-the-bag if you are working too hard. Just slow down and take it easy, then you don't overheat and aren't going to be soaked in sweat. It ain't rocket science. When I go out in the proper cold or wet on a bike I'm usually wearing a roadworkers traffic jacket with reflective stripes all over it. You can pick them up for £20 or less in both padded and unlined versions. I've got one for messing around in that I've had for five or six years. It gets washed when it starts to look really grubby, maybe three times a year. I don't take any notice of the limit to the number of times you are supposed to wash them, although it's usually x25. I'll just keep using it on the road until the reflectives aren't too effective any more, then it will get relegated for winter bramble clearance, car tinkering jobs etc.
& some of the cheaper hi-viz stuff from markets isnt always as reflective as it should be, so buyer beware. I would expect stuff from the likes of Arco/screwfix etc to meet the relevant BS standards
