I have three builds in AICS 2 chassis and have been very happy with all of them. That said I have been kicking around the idea of moving one of them over to an AX but it will NOT be my 338LM. There is no AX chassis currently available to take the 338LM and although it is possible to modify the 300WM chassis and mags to run 338LM I doubt I would go that route. There is also the question of getting whatever 338LM action you have to fit that chassis as well.
Now for either my .308 or 6.5x47 rifles I may still at some point move one over but seeing as how both are running Stiller TAC30 AW actions and I can use the AW mags other than the "cool" factor there is not much making me want to go there yet. On top of that because of the railed front chassis I would need to buy higher rings which I am not thrilled about either and the likelihood of me running NV any time soon is pretty limited so I don't see a need for the rails. I can always add an IMUNS to the AICS 2 if I needed too.
Have fun with the build, it is kind of like Lays potato chips - bet you can't build just one!