As far as fun, yes it is fun, most mages are; and having a spammable hard hitting skill like cursed blades comes in very handy.
As far as end game ,well, you won't find any mages in end game except M/Wl because of a debuff skill.
As for PvP, M/R can be decent, the fear affect when hit can be pretty fun, but you do have to survive that hit.
But realize you will have to tier two weapons to get the most out of dual weild.
On the plus side, you can swap to R/M which is OP.
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