Laptop - some, Desktop - all
The use (or not) of Luclin model does not affect lag (in the traditional sense of a delay in data transmission from server to PC). Using the models does require more graphic rendering time (higher polygon count) and I think the textures are much larger. If you have very little video RAM, slow RAM, or an old graphics processor (or handicapped one, like those found in laptop) you will experience lag-like moments in any highly populated areas. The computer may have to pull textures in from main memory (or worse, hard drive cached memory) to render the screen in which case the frame rate plummets. It's been quite a challenge at times to keep the frame rate up on my laptop which is where I prefer to play most of the time. The fewer polygons, the simpler textures...the better.
I like the overall graphic improvements in the game. The modelers tho' really need to keep supporting low-resolution support as I suppose the most loyal players are less inclined to upgrade (our) hardware just to keep playing. So far...so good.
I don't know what they did to "fix" Freeport, but the initial framerate drag has been largely eliviated...good job folks! I haven't noticed if the Ro's have gotten better.