Time-unlimited access to the licensed XSMP major version and all relevant bug fixes. Eligible for future paid upgrades to major versions. If you are absolutely sure you won't need any future major version, then the Box license could save you some money in the long run.
Repo and Studio editions contain scenes for all supported rendering engines. Professional edition contains only for the selected engine (for example, selected Pro V-Ray - include only scenes of V-Ray Material Lab).
Studio edition contain Pre-built Material Presets Libraries for all licensed version supported rendering engines. If your major version term overlaps with a new release or update of Presets Library, your XSMP Studio edition license will be eligible to obtain the new Presets Library (when it is created) for other rendering engines, which can be used for the duration of your license period. Professional edition contains only for the selected engine (for example, selected Pro Corona - include only Pre-built Material Presets Library for Corona Renderer).
XSMP Material Manager can handle any material supported by 3ds Max. Only generating preview is limited to supported rendering engines. Repo and Studio editions can render preview for all supported engines. Professional edition - only for selected rendering engine (for example, selected Pro V-Ray - can render preview images with V-Ray).
Prices do not include taxes. Available discounts depending on the number of licenses.