I have two highchairs both ends of the price spectrum - a stokke tripp trapp and the ikea antilop. We use the antilop at the table in the garden!
The antilop is great. Totally hose downable. The inflatable insert is really useful when baby is still needing a bit of support, and quite portable if you find you need to take something with you to pad out highchairs in cafes etc. it really is an excellent highchair, don't be fooled by the low price...
But I'm also really glad we've got the tripp trapp. It's our 2nd actually as DS1 still uses his, at 3.5 as it is doing what its supposed to, growing with him providing him with a seat and platform for his feet at exactly the right height for him, and will keep growing with him until he can put his feet firmly on the floor and sit in an adult seat. When we eat out or at other peoples houses I see him looking all awkward in other chairs and I'm so glad he doesn't compromise at home and has a chair that always fits him right. So while we thought long and hard about getting the first one, it was one purchase that was a no- brainer for DS2. I do have spinal problems and am probably more paranoid than most people about ergonomic issues though, in case the DC have inherited my problems.
So if you are on a tight budget, yes, yes, yes, get the Antilop.
If you are happy to spend or a family member has offered to buy a significant purchase, I'd go for a tripp trapp over a fancy buggy, it will last you a LOT longer.