I'm using a number of G-F locos, both old and newer vintages, steam and Diesel, traditional and modern eras on my layout. It's all British prototype at 1:148 scale. The original models were made in England, but, a few years ago, the company became part of Bachmann who have been upgrading the line with new mehanisms in the locos and greatly improved paint and lettering. The newer models are quite nice, though I must say the motive power still doesn't operate as smoothly as Kato or even Bachmann's own Spectrum line US models. However, they have a couple of new locos coming out soon with a new mechanism that looks promising.
If you Google Graham-Farish, you'll get to the website for Bachmann Europe and can follow their links to see what's out there now.