We bought Tripp Trapps for our twins. Initially we were disappointed, as they didn't seem to be that comfortable for young babies (ie 6 months). They seemed to lack support for when the baby can't sit up straight any longer, difficult to get in & out of (until you & your baby gets the hang of it I think). However, now we couldn't be more pleased (@ 21 months) - I'm not sure when that transition occurred! Perhaps around 9 months old. They climb in themselves (hard to believe until you see it) and love to sit at the table with us. I love the idea that they will take their chair with them when they move out of home.
Very important though - the chairs come with a 'foot extender' of sorts - to stop the chair from tipping backwards once the baby starts to push off from the table. The chair will slide and not tip when this extender is fitted. It's a little ugly but I imagine we can remove it once the baby kit is removed from the chair.
Also - check your table height. Our table was too high, embarrassingly we had to get it lowered. Fortunately it was new from Tree & they did it at no cost.
Also, the cushion is a terrible waste of money. The seat cushion gets grotty very quickly, and it's a pain to remove. We use the back cushion because it's pretty (and expensive) but don't bother with the seat cushion anymore.
The Stokke trays are also expensive (sigh, isn't it all) but we got them and they've been very good. It means the kids can eat off the tray without too much stress if they want to, spill a bit of water, tomato sauce, whatever if they want to & it's easy peasy to clean up & doesn't hurt the table. (It sounds like a free for all at dinner, doesn't it, but I really think that because they eat with us, they copy how we eat a lot & it's not tooooo bad)
Having eaten at some restaurants, there is an Ikea chair - don't know what it's called but it's white & has no tray either & the kids love that one too!
I would totally recommend the Tripp Trapp - for about 9 months onwards. If you can borrow or get a different second hand chair for a couple of months until then - that's what I would do.