For #1, we had the kind that straps onto the regular chair because we didn't have room for a stand-alone high chair in our old house. I HATED it. There are several spots where the straps and bosster itself rubbed the paint off our kitchen chair. Soooo much crud and gunk got stuck under the booster where it sat on the chair. And once Tyler decided he wanted to sit at the table, he refused to have anything to do with it so we never got to use it as anything other than a high chair.
For #2, I decided to get an actual high chair now that we have the room for it. The seat height on most models can be adjusted, so I'm hoping we can pull it up to the table without the tray when she's old enough.