I don't have an Epi anymore, but I think the DT25 is a good fit for most electric guitars, because of the flexibility it provides, i.e. 4 different NFL topologies, class A or A/B, pentode / triode - you are almost certain to find an amp sound in the DT that works well with your guitar / style of music.
However, the nanomag pickup is a different issue. The DT25 combo does not really work for acoustic sounds, for me, so I usually use a separate acoustic amp for that. I've seen a youtube clip where someone did get some usable acoustic sounds out of a DT50, using a Variax I think, but the DT series isn't really designed for acoustic. If you are going to be switching between the standard pickups and the nano mag a lot, you might want to consider splitting the signal, using the DT for the standard pickups and running the nano mag signal though something else, i.e. a PA or acoustic amp.
Your ears are always going to be the best judge of what works for you, so try one in a shop if you can.,
Hope that helps