we went to IKEA and Howdens, we were warned away from Wren as the uptick in price (inc. fitting) is not reflected in the quality (that was 2 people telling me)
IKEA was cheap, no doubt, but two things we got held up on: 1) the quality wasnt really that good and 2) the fitter was not keen at all b'cos if something breaks, something is missing etc, and you dont live near IKEA then you get delays and more delays (there are ALWAYS delays, you dont want more).
We went with Howdens, who busted a gut to price match with IKEA (they ended up ~15% over) and the lass was extremely helpful with the kitchen design. One thing that further concerned me about IKEA was that the Howdens designers were a bit shocked at what the IKEA designer had reckoned could be done. Now that it's fitted i am inclined to agree; i cannot see how IKEA's was remotely possible and it was quoted up and ready to buy, i dread to think what problems that would have caused down the line. We were on a treadmill at IKEA, a queue of people waiting for designs so i cant see how the real thought can be given - was really handy to see it on paper though :D. our Howdens is decent quality without being amazing, happy with it.