I’m just going to pop in a link to [Poll] Womanizer - did it work?, it is probably the most comprehensive thread on the forum about the different suction toys and will hopefully be useful to you (though is quite a long read).
I have the Melt and absolutely love it, it is my top recommendation (though I don’t own either the Premium or the Romp to compare it to). It did take a bit of time to learn the best way to use it for me but is fantastic once you know what you’re doing.