As for our ikea-kitchen I can say, that we're very happy with the build quality.
It's on the same quality level like other brands that can cost a lot more.
But on the other hand you can plan/combine the ikea cabinets and pieces freely yourself and with the availability of single parts you can build your own special solution.
Our kitchen isn't that big and we wanted to use the space it has best as possible. All suggestions from other companies relied on their individual standard solutions and changes to that were the costly part.
So we left that ground and turned to kitbashing with ikea.
In fact it isn't that much different from a genuine, complete ikea kitchen.
We wanted a worktop (or countertop? -"Arbeitsfläche") at 105cm above the floor and we wanted a 90cm wide kitchen hood although our cooking zone is standard 60cm -the extra 30cm is for other damp-producing devices such as an electrical kettle, an egg-cooker or a coffee machine. So the cabinets housing the non-ikea kitchen hood were built using a normal hanging cabinet that I adapted for that purpose by cutting out the openings needed and fitted some extra parts in that I made.
We also wanted an oven with specific features and didn't want to give a leg or an arm for it.
So we ended up with an ikea kitchen planned with the ikea self service planing tool and individualised the parts list in an individual face-to-face-meeting at our local ikea store.
After some weeks a lorry showed up and two nice men filled our garage with countless packages and parts. My wife and me together were able to double check the parts list in the time the parts came in -but only we two as a team could compete with the speed of the delivery men -and we finally succeeded. To our satisfaction exactly all ordered parts were there.
Sidenote: We ordered the kitchen some weeks after Russia invaded Ukraine resulting in shortages in many scopes, including furniture. Our ikea agent had a good and a bad message for us:
The good one: All items we ordered could be delivered (that was not the case for some parts we didn't need and especially for items made of birch wood -mainly coming from Ukraine).
The bad one: Less then ten parts couldn't be delivered -we had to pick them up ourselves.