I've worn out two pairs of Kahtoolas - they were the first to introduce microspikes and got the jump. IMO Hillsounds make a slightly better product. I prefer their Trail Crampon Ultra.
It's about $10 more than their basic model, but has the flexible points rather than 2 fixed plates which do tend to ball up under certain conditions.
Hillsounds are somewhat better as they have more points, and the points are slightly longer. More points in the heel area are important on downhills.
But, if you have perfectly functional Kahtoolas, I wouldn't rush out and replace them.