300b, x45, 211, etc.

I currently own a Cary 300SEI my first and only SET ever owned. Curious as to what I'd potentially gain/lose by buying an amp based on the above tubes in the same league as the 300SEI (approx $2,500 used).

I heard a Mastersound 845 with a pair of JM Labs and a Hyperspace that destroyed the Cary Rocket I own... but you won't find one for $2500. BAT would be a different direction, but better... I don't know. I like the Manley Stingray, but it's not quite the same vibe as the Cary stuff. It's funny when you start to think about it b/c after about $2500 used the next jump seems to be $5000-8000; Mastersound, OTL's like Atmosphere or Graaf, or seperates which would be the same as what you've got, but with more power but not necessarily quiter b/c it's a single-ended tube amp.
Personally i think the Cary 300LXI has poor dynamics and weak , rolled off bass. Depending on your speakers, any 300B,2A3,45, or 845 should be considered. Do some auditioning with your speakers.
Thanx for the input. Still looking for impressions from people who have auditioned different SET tubed systems on the differences.
Your question is perplexing: what exactly do you want to know?? The product differences? There are very many products using the tubes you mention... The difference between the tubes?? If so, it's difficult to say much more than that the 211 is more powerful & slightly more extended in its linear operating region than a 300b. The 845 is also a more powerful amplification tube... They use different voltages and output trannies. Ultimately however, the sound you get depends on the circuit as a whole -- not only the tube.
You're listening to a 300b already...