What are the advantages and disadvantages of purchasing new wheels for your car?

What are the advantages and disadvantages of purchasing new wheels for your car?
Many people purchase replacment wheels, including both rims and tires, for their vehicles. The advantages are that you can improve the look of your car. Many people, especially for trucks, replace the tires that is appropriate for the use. Some people want tires that are better in snow or mud. Some people want larger tires--again, a big advantage for trucks. Some people will swith to or sometimes away from run-flat tires. Some people with fast cars will buy tires that are designed for fast highway speeds and for maneuverablilty.The disadvantage is that people don't do their homework and buy tires that are NOT appropriate for their vehicle. Some SUV, such as the Explorer, must have the right kind of tires to prevent roll-over and accidents. Some install wheels that are too large and will rub against the wheel well or limit their steering capability. One big disadvantage for buying a special sized tire is that you will have a difficult time replacing it. Suppose you are on a weekend trip and run over something in the road and shred your tire. You may have a space-saver spare tire but those tires are LIMITED TO 50MPH Speeds. If you have a very unusual tire with special markings on the walls, then you will NOT be able to buy a replacment tire---especially on a weekend.