I don't have a hasbro E-11 to compare with (and I'll never get one either!). Sound quality is fine. The little brother version can record in 8 and 12Kb sample rate for a slightly higher sound quality sacrificing length. Although 50 seconds is far more than I need for my 2 second blaster sound sample. The speaker included is probably better than the one in a hasbro, but I can't compare as I mentioned. And it easy to replace with a bit of soldering.
The sound is activated when the button is pressed and stops if it's pressed again while the sound clip is playing. In the software it's possible to change to a loop started and stopped by button press (not needed in a blaster though).
The big brother version has more software settings for what happens on button presses, but I haven't played around with that yet. On both kits there's a small red LED flashing while sound is playing. I suppose that you could remove it, and hook up some wires to the LED or a bigger one mounted somewhere else. But it will flash, not shine continuously as you might want for a laser effect.