@MissTina Another great question!
When snow balls up under your crampons it is not painful, however, it is at best annoying and at worst hazardous to your footing. Basically, 'snow balling' is simply snow building up in the open space between your crampon spikes...think about it like when using a cookie cutter and the cookie lifts off the counter and stays inside the cutter.
This phenomenon typically occurs in deep, soft, wet snow. If you're using your crampons on ice or hard pack snow it is normally not as much of a problem. Some mountaineering crampons come with anti-balling plates, which allow the snow to be pushed out from between the crampon spikes with each step. The trail crampons you are looking at don't normally come with anti-balling plates.
Crampons are designed to have their points grip into hard surfaces (ice, or hard pack snow). An important factor in thinking about crampons is the depth of the snow: is the snow too deep for your crampon points to grip? This is why mountaineers often get an 'alpine start' (leaving well before sunrise) so that the surface of the snow is harder and they sink in less (it is also safer from objective dangers like rockfall and avalanches).
If your primary use of crampons is for hiking on trails and to carry with you in the event that you encounter ice and snow, then I don't think you'll need to worry about the anti-balling plates. I would definitely recommend a good pair of trekking poles if you haven't invested in them yet! If you are going to be hiking specifically on snow in varying conditions, I would recommend looking at a pair of snowshoes (they give you traction and floatation on snow). If you are hoping to travel vertically, in the alpine, with potential for glacier travel in addition to snow and ice, then crampons with anti-balling plates would be a good idea.
Hopefully this helps, keep the good questions coming!