I spent the gold to exchange one of my spells last night to try out the new Sonic Blast. Granted I was playing around with it on a level 20 bard with a decent CHA score so your results may vary.
1 - I like the look of the spell. It looks like the mindflayer spell. I even like the icon of it.
2 - The stun rate was really good. I don't know if I was just lucky with mobs because I was over their level but I was having a high chance to stun things with it. The stun only lasts a few seconds and does not cause auto crits but for a level 1 spell I really like it. The damage was pretty bad for my character but at one point I stunned a rat in the vale 9 out of 10 times. I really like the stun because while it's not as good as others I feel it adds some utility.
3 - The range seems pretty good. I was able to hit things at a good distance. I need to do more testing but I could see it having a permanent spot on my warchanter. Something running just out of reach? Stun him, run up, and smash. Tried of mobs running out of reach of OID?, stun with SB 1st.
I can see every SS taking this as a level 1 spell. I would like to see more spells like it. Maybe an AoE version that does more damage. To be honest I haven't played with the other sonic spells on my bard so I should probably swap in one of those to test the stun rate/see how it compares.