My Lazarro reeds have arrived and I can now report back as promised.
The short version: softer than expected, but not bad at all. They certainly don't play like $1 reeds.
The long version: I play Vandoren 3's normally on alto, and ordered two boxes from an eBay seller. I requested a box of 3 and a box of 3 1/2, even though it's technically a two-fer deal. (I did say if he couldn't do it then just send two boxes of #3.) He did exactly as I asked and sent one of each. I am only reviewing the 3 1/2, since the 3's aren't for me.
All the preparation I gave the reed was to stick it in my mouth long enough to assemble the Buescher alto, then I slapped it on and started blowing.
The Lazarro 3 1/2 is softer than a Vandoren 3 (and I mean a humidity-pack 3, not the older, harder 3), but not by a huge margin. The tone tends toward the bright side, almost as much as the Fibracell, and the response is actually quite good. I was running effortless arpeggios from low B and Bb right up to altissimo G on the C* and Buescher Aristocrat. It's a fairly dark setup on a fairly dark horn, so the extra sparkle in the reed is not a bad thing at all. I just wish I'd gotten 4's, they would have been a better match for me on a C*. Altissimo response above G fell short, but (1) that isn't the C*'s strength to start with, and (2) the reed was too soft. The notes were there if I really pushed it though, and the bottom end is as big as I could hope for. (The Buescher has a better low end than the Jupiter, from :line1: to :lowbd:, but it can't keep up from :space5: on up. It would probably do better with metal resonators under the left hand.)
Soft playing produced the lovely stringlike sound that is the whole point of playing a C*, yet loud playing could be surprisingly aggressive. I had more room to maneuver than I did with the Fibracell when it came to timbre, and way more edge at full volume than the Vandorens ever provide when paired with a C*. If you like a consistent tone at all dynamics, this may not be the reed for you, but if you like the ability to turn it on and off on demand, it is most definitely up to the task.
Switching to the Rousseau JDX8+wedge on the Jupiter 767, the sound is significantly less bright than the Fibracell, and somewhat brighter than my usual Vandorens. It still sounds like a high quality cane reed, much to my surprise. The 3 1/2 hardness is also a touch soft for this mouthpiece, but not as much as on the C*. I had difficulty coaxing the altissimo C# and D out of the horn, which is pretty typical when a reed is just a touch too soft for me. If they had a 3 3/4 (which they don't), it would probably be about perfect. I will certainly keep a handful of these in the case as instant backup reeds. I have no idea how long they will last when going full blast for an hour at a time, but I know they'll play straight out of the box. In the environment where I play the modded Rousseau, "mf" means "mother f***ing loud", so there is no point in even looking for the "mute button".
I haven't messed with Rico in a while, but from my recollection, these are better than the orange box crap by a good margin. I can see why teachers stock up on these -- they're (extra) cheap, they play instantly, and the quality is not bad. Just bracket your order a half-number and a whole number higher than your "premium brand" strength, and you should end up with half of them being playable at least. Maybe more if you're willing to hack on them, but at a buck each it hardly seems worth it. Next time around you can order them all at your preferred strength and get well over half to work for you.
One caveat: I use a Winslow ligature on the Rousseau (though I was not using it on the C*) and it does tend to flatten out slightly warped reeds, to the point where I hardly notice until they're about to fall apart. So you may not have quite as much luck with them playing straight out of the box as I did.
I placed my order with "musicstore4you", so if you also want to split your two-box order between two different strengths, you know who to turn to.