Besides all said, if you want an ESP and want it true to the Gibson in terms of construction, materials, looks and, to a lesser degree, sound, and don't want to part with a large sum for a Navigator, check the Edwards LP line. They can be had for surprisingly cheap if you're getting used, but new is problem because you have to import them from overseas.
Long tenon set neck construction, correct wood choices, premium hardware and Duncan pickups. I've got two and I like them just as much as many of my Lester Standards real deals.
They feel a bit different, and sound different thanks to different pickups, of course. Edwards are not weight relieved but feel incredibly light (or atleast two of mine do), and with the JB on the bridge the sound is ofcourse more contemporary as you'd expect from a higher output pickup. That was really my only issue with them, the JB which I simply switched for a different pickup.
A buddy has a Jimmy Page lookalike Edwards that he put whola lotta love and an a2pro in the neck, and that guitar just completely nails those LZ tones to a T.