My wife and I will be going to Italy in December. We need opinions as to what travel under garments to pack. Should we take garments that are intended solely for travel or would disposable garments be the way to go? I know we will need to layer throughout the day and pack light as we will be travelling by train. We intend to carry on all our luggage in a backpack and daypack each.
My wife and I each use Ex Officio Give N Go underwear. Also, each of us take a set of silk long johns, long sleeved. Some of the merino wool light weight underwear might interest you too. If we are going somewhere chilly I take a long sleeved tee shirt made of merino wool, light weight. All this stuff washes in a sink and dries over night.
Assume you will be near a laundromat about once a week, so your regular stuff will be fine. A week's worth of underwear and socks won't load down your bag and the outer stuff doesn't necessarily need to be washed after every wearing. For three weeks in Italy last October my husband brought his regular underwear and I had some nylon wash-in-the-sink and some cotton. Two laundromat stops were all that were needed, and provided time to review the guidebooks for our next stop.
Silk long underwear is thin, lightweight and warm. I wouldn't bring disposable underwear. I don't buy special underwear for travel, but women's underwear tends to be lighter weight and dries faster than men's.