So I am going to try to respond to everyones posts.
So on the B215XL, I've heard the difference between the 212XL and the B215XL. Yes the 215XL is bigger body but the sound in the tweeter mostly stays the same the quality if you will. The sharpness of the G-734s is amazing. Some might find it slightly harsh but as I expected once in a home theater you'll find things become much more clear. It has that JBL cinema sound, if thats a thing.
I did not test with a sub, as I wanted to compare the bass as well as the 212XLs have zero pretty much. I don't need to cross over with these speakers. I tested vocals from Adele and songs like Dire Straits Private investigations. Then some silly stuff with a lot of bass(yes the speaker has plenty). Testing the highs is where it shines. Now I did attempt to do a rough volume match to make sure I'm hearing it correctly. The 95db vs the 102db is VERY noticeable. I found that the audio was just more clear and more crisp coming from the G-734. The highes felt muffled on the Berry.
Please keep in mind, I've not really heard much that tops the Berries, some things at Mikes GTG's have but we are often talking DIY Fusions or things into the thousands of dollars. Please don't take this as a knock on the berries.
The G-734 are technically vintage but they are extremely similar to the 3677 even use the came CD and same horn dispersion and the same size are almost the same. The LF and the crossover are different it crosses over at 1.5khz but outside that it's almost the same speaker. Some will say the cross over is different and it is but its a pro speaker so I don't think quality between the G's and the 3677 are going to mater.
Nothing is wrong with the berries keep them, I like them and they are still the first speaker I would tell someone to buy.
I got them from Guitar center, they are old looks like ~1991. They are almost in perfect shape also, which is helpful, I need to find a third in good shape. I only paid ~150 each so that's pretty damn cheap.