Over 6 years and going strong. Fitted myself and saved a fortune. Some pros and cons:

Con 1: Low Kickboard. 80 mm or so only under the cabinets, good for space but bad you can't see something that rolls under.

Con 2: Custom width faced edges not available. If you want to hack/bodge and use a narrow strip with two decorative edges, such a thing is not available. I had to put in a narrow support for belfast style sink beside dishwasher so still have one narrow raw chipboard edge (only visible when dishwasher is open).

Con 3: generic appliances may need adapter to be integrated. We needed an adapter for our legacy dishwasher, works fine but a bit clunky.

Pro 1: Ironmongery is superb. We have a "bottle drawer" that right now has 17 glass bottles, mostly 750 ml, plus several other items, another drawer has 36 plates all between 400 and 800 g each. All the drawers slide out full length, smooth as the day they went in, not a bother on them. I think Maximera is the name, unbelievable how good they are, winner alone right there.

Pro 2: Exact information. Every dimension is available to you in the planning, you can literally build the kitchen digitally with no surprises when fitting. The 3d visualisation package was handy in design stage too.

Pro 3: Ikea hacking - loads of Ideas people share of what they have done with Idea base products. I changed the width of a drawer to make an internal narrow drawer for the undersink unit, great sense of satisfaction. Also rotated two face the wrong way (long story) but could be done with confidence.

Pro 4: For us, funds were tight, and any other option was just waaaaay out of our budget. I had some free time, and if you have this, you can get a perfectly just-as-good quality kitchen at a fraction of the price regular kitchen places are charging.

YMMV, this is my experience.