I purchased a few pairs of “thick tzitis” tallis katan before yom tov and the tzitzis were *not* those typically found on a tallis gadol, but about 1/2 as thick (my casual estimate).
It could be that since the beged of a tallis katan is of thinner material than that of a tallis gadol, the stress of heavier tzitzis could lead to premature ripping of the eyelets.
One, of course, has the option of purchasing the beged and tzitis separately and tying one’s own tzitzis using a talis gadol set as an experiment. Tzitzis tying is actually not that difficult to do, but it does require time and patience, two things I find I have less of as I get older (sigh).