I'm in the process of researching a trip to Wales, as my husband and I have traveled to England, Scotland and Ireland but want to make sure we see all aspects of the UK. I've been to Cardiff before, but aside from that really didn't know much about Wales.
I picked up the Lonely Planet guide hoping to get some ideas and inspiration to plan the trip. Unfortunately, I just wasn't inspired by the book. I started to doubt whether or not we should really visit Wales based on what I was reading. The book totes walking tours, etc, but I felt like it really glanced upon other beautiful sites like the cairns, castle ruins, and so many other sites. They were in there, but the layout just seemed jumbled together with no distinction of 'must see's!'
I think I was spoiled on our last trip overseas where I relied heavily on the Rough Guide and Rick Steve's. Neither book had 'everything' that I needed alone, but together, they were the perfect resource to make an amazing trip. I'm sure that the Lonely Planet guide works for some, but personally, I love the layout of the Rough Guide with the two columns, bolded sites, ranks of 'need to see', etc. In the end, I returned the Lonely Planet guide and exchanged it for the Rough Guide. Definitely check both out before making your decision as you may prefer one layout over the other, I just thought the RG was more user/traveler friendly.