The modified maglight that Elektrolumens makes is a dedicated single unit if I understand correctly, yes? You can't take the head out and drop it into any other maglight because the maglight has been modified extensively to make it work with the EL module? If this is true that would be a deal breaker to me.
The Malkoff unit will drop into any 2C to 4D unit and run up to but not exceed 6V, 4 high current capacity rated NiMH will run it very well and the host is not a concern. I like the EL unit but I think the versatility of the Malkoff, its robustness, true simple drop in, make a it a great deal. I am of the belief that its a good 700 real lumens out the front which is fine for me, using at least 3 C cells or greater based on what I see comparing it to multiple 220 lumen (measured) lights. I have switched it in and out of my 3C, 4C and 4D lights back and forth with no problems at all, and that is part of the beauty of it. When I want to use it for tactical shooting practice it goes into a 3C, when I want to light up the neighborhood for potentially several hours, it can go into the 4D. Yeah it cost a little more, but to me its worth every penny.
And this is in no way a put down of the EL unit. If you get a dedicated P7 unit and it works for you and you find that a good value, I ain't complaining. We all have different needs and values in the arena of photonic distribution.
My guess is that the EL unit probably puts out just a little more out the front lumens from the P7, maybe a total of 800, Not the end of the world difference to me.