We'll be staying on site for our next trip and won't have a rental car. I anticipate that there will be a few times when we'll want to take a taxi to some destinations for convenience. I have a 2 year old son and want him restrained, but we will not have his regular car seat with us. Has anyone used one of the "travel" car seats that are sold through One Step Ahead? I know that I am not calling it by the right name, but it claims to transform any regular seat belt into a 5 point safety harness for children. From the picture it appears to be a rectangular seat with a 5 point safety harness, but I am skeptical (although I suppose it is better than holding him in my arms and hoping that he doesn't become a projectile). Thank you!