Our DIY kitchen was delivered on Saturday and looks very good. The delivery men said if we find any marks or knocks to the cabinets to ring straight away and a new one will be delivered within three days as they have three trucks delivering to London each day. The cabinets are built i.e. not flat packed and you can opt for dry assembly e.g. not fully glued cupboards for areas where the builder may have to do some adaptations e.g. we're putting a 600 wall unit around the boiler.
I designed ours using their online planner and then had a day trip to Pontefract after first lockdown and went through it with one of their consultants who suggested some very good tweaks which ultimately saved me even more £. I had subsequent questions and their telephone customer service has been excellent although I know they are really busy and sometimes you have to submit an online query rather than phone (they respond within 24 hours). You can order sample doors to be sent to see the quality. My only criticism would be their delivery date system - you are given two possible dates it could be delivered on, and these are confirmed only a few days before it is being delivered. I'd make sure you get it delivered the week before as they deliver from M-Su every week and if you request your week it could come on the Sunday of that week i.e. right at the end of the week, which might not work with your builder's timings.
Our friends have just installed their own DIY kitchen and are very impressed. They had a damaged cabinet but said it was very quickly replaced.
We paid just shy of £8k for 38 items which comprise the kitchen, including quartz worktops (our kitchen is 5.4m x 2m). Magnet quoted £12k but didn't have the range of sizes in cabinets I wanted. Wickes really couldn't be bothered and quoted £9k, not including worktops and they'd missed approx 1.2m of the kitchen off the plan completely! We looked at Ikea and I didn't really like any of the styles plus, when I visited the DIY showroom, it was clear the quality of theirs was much better. Our builder is impressed with the quality too.
It felt like a bit of a leap of faith for me to order from them, but so far, so good.