Q. What heel heights do the shoes come in?
A. Comme il Faut shoes come in 3.75" (9.5cm), 3.5" (9.0cm) and 3.0"(7.5cm) stiletto heels. NeoTango Shoes come in high stiletto heels (8.5~9.5cm), 8.5cm regular heels, 7.5cm regular or stiletto heels and 6.5cm heels. 

Q. How are the heels measured?

The heels are measured along the axis of the heels. The photo above is provided by NeoTango shoes. For Comme il Faut shoes, the heels are placed a little further back and so the measurements of the heels will be slightly different for the two brands.

Q. Why are the heels so high? Why do we have to wear heels to dance anyways?
A. Even though Argentine Tango dance is based on the "Walk," it isn't necessarily easier to dance in flats.   The heels help you in the following ways:

• They make you look nice and elegant, a very important element in this dance.
• They help you balance in the right place; when dancing, our weight is slightly forward compared to when you're walking on the street.
• They make it easier for you to walk backwards, which is what followers do 90% of the time during this dance.
  
  Some dancers put their heels down for each step they take. Others are always on the tip toe.  Whichever way you dance, the heels help you maintain your axis more easily!
  

Q. Is it okay to use dance sneakers or low heel shoes for practice/class and wear high heels for milonga?
A. It is okay but not recommended. Balance is a big part of dancing tango well and when the heel heights change, the way you balance changes.  You also need to practice dancing in high heels.   

Q. What is a "STILETTO" heel?
A. A "stiletto heel" is a long, thin, high heel. It is named after the "stiletto dagger".  A stiletto is a short knife or dagger with a long slender blade of various designs primarily used as a stabbing weapon.  The Italian word "stiletto" comes from the Latin stilus meaning: "a stake; a pointed instrument."

Stiletto heels are sometimes defined as having a diameter at the ground of less than 1 cm (slightly less than half an inch).
Stilettos give the optical illusion of a longer, slimmer leg, a smaller foot, and a greater overall height. They also alter the wearer's posture and gait, flexing the calf muscles, and making the bust and buttocks more prominent. (Wikipedia)