The real answer to this is 'Whatever works for you', but many go overstable. Lots of people like Predators and Firebirds for this shot. I don't have as much of an arm for overhands so my best ones have been with Valkyries. It depends highly on the thrower.
For tomahawks I like using the Defender from Quest. It has a small rim so it's easy to grasp and it's super understable so when you throw it produces a predictable barrel-roll type of right to left flight (assuming you're right-handed).
My absolute favorite disc for thumbers is the Z-Avenger. (I know, most people probably think it isn't quite stable enough, etc. But, it is the absolute best UD disc I have found to date...and I've thrown a lot of UD over the years.) The Avenger us unquestionably the furthest flying, controllable disc for thumbers I have found to-date. I also use a Champion Monster and Champion Firebird on occasion and I would recommend any of them. (I have aces with the Monster and Avenger, if that says anything...)