Are you going to buy the film in the UK or bring it with you?
In Lincoln I can buy Ilford B&W film and Fuji colour film only. I mostly buy my films through the Interweb but if you are on holiday, that might not be practicable.
Also, what are you going to be using the film for? I am currently using Harman 100 film for my street photography. I find ASA 400 film a little too fast giving me too great a depth of field - British streets can be quite reflective of light in the summer.