RPM arms will work on any LST based truck, whether its Aftershock, xxl or whatever. They are bolt on for LST1 and aftershock. LST2/XXL have wider a knuckle and a-arm so RPM makes a spacer to use their arms on those trucks. BTW, I can't fault the MGT for much, but I do like the handling of the LST based trucks better.
An LST2 with Muggy suspension conversion handles even better. With the right engine and gearing combo, it would be a good track truck. Probably not real stiff competition to the Revo in terms of speed but the Revo weighs a good bit less than the LST2 does.
RPM arms are a good investment, but the turnbuckles that come with them are just mild steel and will bend. I cartwheeled one of my LST2's and bent a turnbuckle. The Lunsford turnbuckles are about $40 or so. I havent upgraded these yet, but I will in the near future. The bonus with the RPM arms is having that aditional camber(?) adjustment that you dont get on the LST platform trucks.