I have not heard a peep about the MGS lately. And I had been following it too, since it was were my belief in the sucess or failure of the stryker was hinged. Hell, if wheels were the key (lower maintance costs and quicker in theatre transport, etc.) why not look at the french? Bigger wheeled guns they did well(or at least alot). If 105 why not pre-existing 90mm or upgrade to 120mm? I believe the crux of the matter was the range of ammo for the 105mm and some arbitrary AT capacity. Put a decent turret on the IFV stryker (25mm and an AT missile) and put your 155s on wheels and you don't really need the MGS.
Reed