It's been a very successful weapon for me so far. Win or lose in battles, I perform well in my matches with it. The wall has been surprisingly useful, I've been getting a lot of combos with setting down a wall, and immediately taking out an enemy who I manage to trap/cut off from me.
I've been mainly using the semi auto fire on the weapon, only using auto fire for laying down ink when no enemies are around. Since I've used the octobrush so much, I'm used to tapping the fire button a ton for a weapon, so that's a hurdle I haven't needed to overcome. The great accuracy of the semi auto has been giving me great success in battle. I can tell many people don't know how to approach this weapon well yet. Combined with the stingray, this weapon is a long range terror, with a bit of a counter using auto fire up close should I get desperate.
This is definitely my favorite new weapon they've introduced in Splatoon 2. Most of the others (Clash Blaster, Gootuber, Flingza, even the brellas) did not click well with me, or most others from what I see. But The two fire modes on the Squeezer is not only fresh, but actually viable.