Last time I checked, it was going to be a japanese dub, but don't know if they have confirmed the VAs. Though there isn't much to worry about in that aspect, one thing Japan stands out for (other than animes, tentacles, and a creepy love for Dating Sims and similar games these days) is excellent VAs.
One bad thing about the japanese dub however, is that there aren't many japanese people that know RT or the people that are part of it, so they may not get the references or actor allusions, sadly.
And if it's subbed, people will protest. Just like when RWBY was uploaded in Crunchyroll for being so animesque to be considered by people to be a true japanese anime. The people hated the voice acting and requested the "original" japanese dub.