Once you have tried them. . . .
"Went for the 2 smaller pieces. They work really well in cracks that are not 100%even (how many actually are??). Been pretty impressed by how much better they fit in their size compared to the same size in x4. Not sure about the use of the bigger pieces since they alreadyhave a wider range of sizes in other, non off set models, to move through, so maybe not as big of a difference in how well they work?"
