• Crossed toe picks

This will help reduce slippage in the ice when you pass an angle of 20 degrees.  There are different size toe picks for different needs according to your level.

• Square toepicks 

Carbon steel blades in general are less noisy than stainless blades.  However, Stainless being harder steel (hence why they are noisier because they tend to resonate more) do have a better longevity for the life of the sharpening.

• Extra glide

For extra glide, stainless steel blades do a better job than carbon blades UNLESS they are tapered blades like Gold Seal's  from John Wilson (IOW's  wider in the front  and narrower at the heel.  Another advantage to a tapered blades is the ease of spins.

• Dance and synchro 

These blades have very different characteristics than freestyle or combination type blades.  The heels are short allowing for mohawks to be done without having to swing the free leg further to avoid the blade.  Toe picks are much slower so you it eases the noise of the toe pick when pushing forward into the ice. Another aspect that some dance blades have are a slimmer edge.  This allows for an emphasis on edges and turns (like a hockey blade).  Usually carbon blades are prefered in dance as they are quieter in the ice, this is not unamous, but like I said, usually.