After Left Unity, Breakthrough, Peace and Justice, Social Justice Party, and Transform, I'm sure this one will work out.
More seriously, I'm glad they're pursuing this. Everyone involved will be happier representing their views more authentically and Labour will be better off while freed from their influence, while the electorate will be presented a wider range of choices — and I suppose it's possible they won't make a pig's ear of it and that the two-ish party rigidity of our system could be broken, serving our democracy for the better.
Looks like a win-win-win-win to me.