I am very lucky and own a Martin d-15, I was looking for a second guitar to use for open tunings and researched the Martin X series, Sigma, Epiphone and Harley Benton guitars. I didn't think this could be much good because it was so cheap - but after looking at a lot of reviews and videos, I thought I'd give it a chance. I thought it would be thin and lacking in a quality sound - but it has really knocked me out.
It's not a Martin D15, but it's pretty close, considering the price. I've also compared his to a Yamaha F310, which is also a great guitar for the money, but while the F310 feels weedy and insubstantial, the CLD-15M feels like a real guitar. Solid, robust, the tone rings out and resonates. It's louder than the Martin and more "brassy", it lacks some of the subtlety and nuance, but then it's a lot cheaper!
The bridge pins are pretty horrible, but I think to replace these it's going to need the holes reaming out as they are a non-standard size. The bridge and nut are good though. The action is great, very solidly playable all the way up the neck, some slight buzzing on fret 3 on the A string when I really hit it hard, but nothing too bad. It feels very solidly put together.
The down side of this guitar is the idea that, if this guitar is so nice at only £150, then maybe all the other Harley Bentons at this price are also nice - I'm going to need more space for guitars!
Edit - 6 months on and I've put 13-56 strings on this guitar, adjusted the truss rod for the heavier strings and replaced the bridge pins. I used some graph-tech pins that I already had and sanded them down to fit - it was easier than I had expected. Now it sounds amazing! I recently did an online gig of Roy Harper songs using this guitar in DADGAD and my Martin for standard tuning and the two sit side by side quite comfortably.