There's virtually no difference between it and a 508 except for it comes with the v200 interface instead of a wired cable Which is actually better because you can use the v200 interface. For SPS2 and FDRS If you can swing it financially the IM2 has the diagnostics and comes with essentially what is a XP 401. I think it's a better deal than the 508 myself as you get the 508 plus some extra functionality due to the separate interface.

You don't have to pay extra for advanced immo functions any more that's that changed over a year now it's free. You do have to pay for diagnostics tho. Also the im1's VCI is wireless. The IM1 is thinner but has no kickstand. I have the xp1 pro combined with it. The xp1 pro works with Autels PC software. Also updates for the immo software for IM1 cost 200 a year while the 508 cost about 350.