Step 1
Consider there are two wheel types of ab rollers that offer stability. Those with foam-covered handles are more comfortable. That seems to be important.
Step 2
There are different types. Some have two wheels and offer extra stabilization. Others have one wheel.
Step 3
Consider differences in construction. Is the handle made of steel or plastic? If it is made of plastic, what is the gauge or thickness?
Step 4
Is the grip textured or smooth?
Step 5
Consider comfort: Is the grip padded?
Step 6
Consider durability. Will it break during heavy or intense use?
Step 7
Some models have foam-covered handles. Other models have handles made of rubber.
Step 8
Some models have adjustable handles. Others can be disassembled when not in use.
Step 9
Consider capacity – how much weight can the roller handle?