We've got the Ikea Antilop to and it's the best highchair I've ever used - and I've tried quite a few at friends houses, in pubs etc.
It's easy to clean, very light, and the legs come off for travelling.
The tray has a lip on it to stop food rolling off onto the floor.
Without the tray, the chair pulls right up to the table so that the baby can join in meals.
The baby sits properly upright in it. In so many others, especially the padded plasticky kind, babies, especially younger ones, seem to slump back in them, and I think this is a choking hazard.
Your baby won't ougrow it - my 3 year old still fits in mine - not that he uses it really but he likes to copy his brother every now and again.
The lap harness is effective but much simpler than other and no shoulder straps to get covered in food.
And all for less than £15 - what more could you want!