If you were writing reviews to show your opinion of something in English class and used "I," you'd be marked down. I know it because I have many such old rough drafts of essays from my childhood where that's marked. Being that it's a review, the point of view is already obvious and one doesn't need to keep saying things like "I like," "I think," "I enjoy."
However, this is a site for sex toys and their reviews and a normal person would use "I" to talk about something constantly. I wouldn't trust an upright, "proper" review honestly. It feels like someone isn't being genuine and is simply trying to make me purchase something.
So, use all the I or i or eye you want.