We have used this high chair (along with the infant insert seat) since my daughter was 6 months old. She has always seemed comfortable in it. I primarily like it for the wood design and the fact that it turns into a toddler/child chair that can pull right up to the table. The infant insert is squishy plastic that wipes clean easily. Unfortunately, the hole in the seat where the crotch buckle threads through is right where food falls when she drops it in her lap. So we have to take the insert out after every meal to clean it. Also, the insert is only secured by velcro to the high chair. In practice, that was never a problem, but in theory it just doesn't seem secure.
The instructions specify that the seat has to be at a certain level when using with the infant insert. But after the first few months of use, my daughter grew taller and the tray was just too low. So I lowered the seat. Nothing bad happened, and it fit better.
Now let's talk about the tray, which we used for the first several months. It has a plastic cover that snaps on and off and is dishwasher safe. That is great. What is not so great is the fact that it takes two hands to slide the tray out, which leaves no hands to hold on to the baby. Not so great. Other high chairs have a one-handed lever thing. Why not this one? Also, the tray latches are fiddly and plastic, and one broke easily making it even harder to get the tray off.
When my daughter was tall enough to sit directly at the table, we took the tray off and haven't missed it. Now, at this stage, I really have no complaints about the chair. It is great - looks like a normal wooden dining chair but is the perfect fit for my 15-month-old to sit with us at the table.
If I could afford it, I would purchase a Stokke Tripp Trapp over this seat. However, for the price (and considering I got this one for way, way cheap off craigslist) this one is a great alternative. We'll use it for a long time.