The .in will be a much stronger force and will also be less confusing to people who are familiar with the single extension. I am not sure how it differs from the .co.in or how that even came into effect, but believe that the names you chosen will be of use for some people. I just wonder about the integrity of establishing these and then selling them. I know that in order to buy a name many people look at what the site has to offer in order to determine if they really want the name. Most of the time they will find alternative names unless they are a very big company, as most people cannot afford the high prices of domains that have already been registered.