Yeah, I've used a bunch of other reeds on my STM NY and they do fine. My usual strength is a hard 2.5 or a shaved down 3. Guess if I had my druthers, I'd like a 2.75 or thereabouts. I've used Vando Java Reds, Greens, and ZZs with much better results. Rico Select Jazz and Royals. Hemke, La Voz, Zonda, and some others. None of them died on me like that whole box of Blue Box did. I don't think they were seasoned properly but that's just speculation on my part. Sometimes that happens. A reed is dead out of the box. Put it up and for whatever reason, come back to it in months and whazup! It's much better! Gotta love cane reeds, eh?A 7 doesn't seem like it would kill a reed that quick. A 10* probably would
I'd switch to a different brand. Rigotti and Link work good together. A Vandoren blue box 2 is probably a 2H or a 3S in a Rigotti. I like the idea of more increments in strengths. I'll practice on a 3H and play 3M on a gig because they play well right out of the box.
I play a 6 Link and reeds last a long time for me. I use a few in rotations which may help.
You sound great ..I currently play Rico Royal 2 reeds on my Florida no USA 10* for a few years. Used La Voz medium before, but lost my practice room some years ago and discovered that the RR 2 reeds performed easier with less practice and also made my sound darker (also used Rico Plasticovers 2 for a while).
The softer reed makes (for me) the sound more flexible, but intonation more tricky (especially in the higher register and altissimo). In time you will learn to control that better. I play a single reed between 4 and 8 months.
I've a ton of soundclips on my SoundClick page. Here is my latest recording on an 8 month old Rico Royal 2 and the Florida 10*: