I went - TWICE - and it’s approx 4.5 hours (one way) for me! When I placed my order, the staff member commented that I lived closer to France that Doncaster (he looked up my town on a map as he’d never heard of it).
Back to your question… yes, it was worth it, for me. I didn’t know anybody else who had used them and I wanted to get an idea of colour, styles, quality, etc (and since then, my kitchen has become the place friends/family come to so they don’t have to make the journey).
I’d say they have the most on display out of all the kitchen showrooms I visited so I got layout ideas as well as being able to see various cupboard widths, depths, inners, outers, drawers - you name it, you can probably see/touch it in their showroom! The larder cupboards were really useful for me to see in person.
They also have the biggest selection of cupboard/drawer widths - from 300m going up in increments of 50mm if I remember correctly which meant that I have no “filler” items such as bottle racks, or tray shelves!
I bought a couple of door samples home (paid for, but refunded when I ordered) as well as some smaller samples of the cupboard inner finishes.
Also, they don’t have designers/sales people - hence the lower prices, but that said, the 2nd time I went at a quiet time on a week-day (stayed in a Travelodge not too far away) and there was a really helpful member of staff that checked over my plan/design and helped me input my order on one of their computers - useful as I’d overlooked the need for a couple of end panels.
5 years later I’m still pleased with my kitchen, and it looks almost as good as new.