Disk Brakes - expensive brakes, used in all weather conditions to STOP a bike. Will not contribute to rim wear in bad weather. Tandems are an ideal solution for partners of different riding abilities to ride together, if they are able to communicate well. Tandems are also great for blind stokers or stokers with some physical limitations that may keep them from riding a single bike. And tandems are really great for two strong riders looking for a new challenge.
Tandems really fly on flats, rolling terrain and downhills.
Climbing is considered to be more difficult, but a tandem team with lots of practice can climb amazingly well. Tandems are good for touring because the extra weight is much less noticeable than on a single, but be aware that there is HALF the luggage space. Of course everyone knows that when touring you will FILL your bags, no matter what the size, so this could be an advanatge. Communication is the absolute key to riding a tandem. It has been said many times that a tandem can make or break a relationship.