I have an etek3 am and looking back I wouldn't have gone any other direction, over all just great never have had any problems, just make sure you understand everything your doing and don't assume you can do things that your not sure about.
im really set on buying it read reviews on it and it just sounds amazing like right now im rocking a proto slg but etek3 sounds so much better the only problem is what color to get lol they all look so sexy lol.
If you have any plans on upgrading the board in the future then buy the AM.
Just recently ANSGEAR moved the AM upgrade to the graveyard and i only found two other places that were currently selling it (PE was one). That leads me to believe they maybe phasing out the LT all together. Think a little further than just that first shot.
If you just want an inexpensive marker and do not plan to upgrade -> LT
If you think you might upgrade later -> AM