New to TiVo. I got the Premiere model with 2 tuners. I think the model is tcd748500, it's too small to read to be sure. I have ordered cable tv for the basic channels they are coming to install it next week. I am currently using an antenna and seems to work ok. I understand that you can only use two channels at a time. So if I am watching one I can only record one more. Is only two tuners a problem? It's easy to go back to the store and get the 4 tuner model. If I did get the 4 tuner model I understand that doesn't work with an antenna. Is there some kind of box I can plug the antenna into do that I can then plug that into the TiVo? Or am I then stuck with always having cable?