I'm using the mil model. I compared my 3-12 to my Premier Hunter in low light. The test was resolving a small (6") box inside of a larger(20") box at 100yds. The Premier definitely had it beat throughout the evening, but the margin was very small. At the end of the night the Bushnell tapped out approximately 2 mins before the Premier and both bested my Weaver Tactical 3-15 by ~an hour. FYI that Weaver beat my VX3 Leupolds so badly I sold them all.
The 4.5-18 is really nice, the 18x strains the Bushy glass more than the 12x does, but the extra 6x comes in handy. Eye box is definitely not excessively "tight". The turrets are "good" not too firm or soft, the side focus and mag ring are also "good". I wouldn't describe any of the controls as orgasmic, perfect, or Tangent Theta esque, but they're all very "good". The 4.5-18 is longer than the 3-12 by about 1 1/2", almost all this length is added between the erector housing and the objective so it looks a bit stretched. The reticle is serviceable at the lowends, the 4 mil circle really doesn't help "that much" as it is kind of gray and subdued. Neither of the LRHS scopes really shines in the WV deer woods, but that's where I live/hunt now and I certainly don't feel helpless or hapless carrying one, haha. I drastically prefer the weaknesses of the LRHS line to the weaknesses of any other practical distance scope available, they just work very well. I really like both of these scopes, great rifle sights.