I'm obliged to offer some quick comments, as I have tried each of these strings at least once.
Ytex Square-X 16L - Black is similar to Monogut ZX Black, except the ZX is smooth. The Square-X is a bit less elastic.
Yonex Poly Tour Pro - I only strung up the 1.20 once. I checked the bed with ball bouncing a couple times in a few days. It deflected a lot more than it pocketed and felt very synthetic. I knew I wouldn't like it so I cut it out. Uniquely soft, muted string.
Topspin Cyber Flash - My favorite poly of all time when price is considered. The upgrade is Tour Bite Soft, a little deader and a little softer feeling.
Weiss Cannon Silverstring - Mid-range in price between Cyber Flash and TBS. Not as good spin or feel as the other two.
MSV Focus-Hex - 1.23mm and thicker are very stiff strings. I like the 1.18 black a lot. Basic shaped poly with good spin if you have good technique. It's similar to Pro's Pro Black Force 1.14, except BF is smooth and round, and a great value when you get the reel.