What is difference between lightmass and LPV

What is difference between lightmass and LPV (Light Propagation Volume)? I want to make archvis with using matinee.
- YouTube. This is my first try. I enabled LPV and disabled Lightmass (as its described here: A new, community-hosted Unreal Engine Wiki - Announcements - Unreal Engine Forums). I would like get nice soft shadows from outside direction lights and few from point and spot lights (I don`t know if all supporting LPV GI or only directional). This is pure material animation but I think about baking GI shadows in Modo and import as tga texture to UE4. I would like mix dynamic GI and baked one. Is it good solution? Which is better LPV or lightmass to my purposes? Or maybe all should be off.

Lightmass renders shadows and lighting (direct and indirect) for static lights. LPV provides some sort of dynamic GI, but the functionality is still experimental, and anyway the quality you can achieve in real time is inferior to the one of baked lightmaps.
In general, if you do not need to change dynamically the lighting of your scene, in order to achieve the best possible quality in archviz project I would suggest to stick with GI.

Here you can find more details about all the lighting options in UE4:

Using precomputed lightmap is not straightforward, according to RyanB in this answer:

To actually specify a lightmap inline
with the current lighting system isn’t
really possible because the lightmaps
aren’t really just simple lightmaps in
most cases, they are directional
lightmaps with some limited
directionality. I think it would be
very hard to get an image rendered
that works. Would require a certain
amount of coding.

I can suggest a method that will kind
of be halfway in between a complete
emissive material and what you want to
do. You can use part dynamic lighting
part lightmap if you do this. Keep
your diffuse how you normally would,
and use your 3d software to render out
a black and white shadow map. Then you
can multiply your diffuse by the
shadowmap.