Recently, I got the chance to try Mame on a later model laptop. I was surprised at the image quality of the graphics. Even more, I was surprised at the quality of the effects presentations of both old and new Mame. Though in older Mame, there was still some slight lack of authenticity (using 75%, 50%, and 25% scanlines) in vertical scrolling games - games run horizontally, hence, horizontal scanlines - the overall look was pretty good. Further, in new Mame - using 75x2 - the look was pretty good, too. I didn't have any special files on hand - like Sailor Sat's triad3sl, or Althor's Scanrez2 (in particular, rotated, to provide horizontal features) - but it seems the high brightness of LCDs is much suited to Mame effects rendering.
I've also been playing around with current Mame and Scanrez2, as well as Sailor Sat's triadsl, on my arcade monitor, with the following results. (Incidentally, they don't look good embedded. Also, for accuracy, remember to click inside the image. And, Mame apparently takes snaps from the raw output. These images were system snaps.)
The first one is Scanrez2. It's pretty nice, particularly with the contrast set to 1.60 to bring out the color and all.
The second is the triadsl, same contrast level. A little dingy.