El34 or KT77?

I read the descriptions on eurotubes's website but all the description there are robonat, all fantastic tubes....but in practice...which are the differences from EL34 (or E34L from JJ..I think it's better than a standard EL34) and KT77?
 
If the KT77's are anything like the KT88's they will have a shitload of low end, and fairly scooped, and the EL34's are more midrangey (a more British tone you could say).
 
I post the 2 descriptions:

E34L: This tube has about 20% more head room than the standard EL34 and it also has a deeper, tighter low end. The E34L is also a bit punchier and more aggressive than the standard EL34 which makes it a Great tube for Matchless, Bogner, Carvin, Peavey and all Marshall amps. I have them in one of my old SUNN heads. Incredible sound!

KT77: The JJ KT77 has a slightly deeper low end than the JJ E34L and they have a nice sizzle on the top end without getting brittle and the mid range harmonic structure is very complex. The clean tone is very fat and full and the when driven to saturation the crunch has more of a chunk to it.

And 2 descriptions they write me in answer at one mail:

The JJ E34L's provide a deeper low end and are more aggressive and punchy than an EL34. The E34L is tighter with slightly more headroom and power with a more aggressive crunch, a very articulate British tone.

The JJ KT77's have even a bit more low end extension than the JJ E34L's and they have a nice sizzle in the top end that is not brittle. The clean tone is very fat and full and the crunch at loud volumes has more of a chunk to it and it's very punchy but not quite as aggressive as the E34L, a great tube for rhythm and solo work if you like the pushed mid and upper mid tone that all EL34 type tubes have.
 
I've got JJ KT77's in my JSX and I'm pretty happy with the tone I'm getting; granted, I haven't compared them to anything else in that amp since I just got it with 'em, but I used to own a 5150 combo with JJ 6L6's, and this baby has a much sweeter crunch to it while still having a comparable low end (though that reported "sizzle" in the top end is pretty painful; I've got my treble at 4.5 AKA 11:30 cuz any higher hurts like hell...but maybe that's just the JSX, as I said, I haven't been able to compare other tubes in it yet).
 
I suppose the best tone I can think of to describe the sound would be on In Flames' "Come Clarity," in my opinion, their crunchiest tone ever.