I have both the InsideOut and the Duo 2. When I got the InsideOut I loved it and it still is fabulous but for me the Duo 2 100% wins out mainly just for the more girthy G-Spot arm. They both “fit” me very well which is always the risk with rabbit style toys but I think these do have quite a bit of adaptability as the base of the arm is so flexible so they will fit a lot more bodies than firmer built designs.
In terms of the suction toy that by default and for a quick guarenteed fix I reach for the Melt comes in ahead, mainly I think because the “head” on it fits me better than any of the Womanizer ones.
You can read my review for the Duo 2 here if helpful to you and I can hopefully answer any questions you have about it or the InsideOut (which being 25% off currently, I can see as appealing!)