Not a guy, but...
My husband has bought quite a few toys for me, and I have purchased quite a few for myself. You name it, it's in my toy box. lol
We have had a lot of conversations about the toys, and only once, early in our marriage, did he have a bad reaction to one of them. He was downright insulting about it actually, it was larger than him. After his reaction, I tried to always stick to toys that were much closer sized to him.
Fast forward more than a decade later...he described a toy he wanted me to go purchase, and it was certainly girthier and longer than any that I had ever purchased. I was surprised by it, and very cautious. But, once we used it in the bedroom a few times, and no bad reactions, I felt comfortable enough to talk to him about it and how his reaction made me feel so long ago. He admitted to me that when he was younger, he certainly had less confidence then when it came to things like that. Nowadays, the enjoyment is in blowing my mind and him knowing that he can do that. It makes no difference to him how he makes my toes curl. It's just a tool to get the job done! He said he even gets a kick out of watching said tools of various styles and sizes in action. It's stretchy btw...it bounces back to size, and I have amazing muscle control to boot
With all that being said, if he is good with using the toys during sex to assist...why not use them in the reverse order?! We do that all the time. He uses the toy on me to get there...and then to get me close to there again, and then he takes the helm himself! He gets excited and gets to anticipate, which makes it better for him, and by having a mostly clitoral orgasm for the first one, and then getting me close to a second one, when he takes over and we get in the right position, I can have a wonderful g-spot orgasm the second go around. And he knows, that is way more fun than any rabbit or any other vibe can do for me personally.