Unlike Matt, I found Calumet in Birmingham useless. For years I used Pelling & Cross, then also Leeds Cameras & Ultrafield, all in Birmingham. We had excellent suppliers. Then Leeds bought Ultrafield. Calumet bought Pelling & Cross, and finally Calumet bought Leeds.
Leeds always kept Agfa APX100 5x4 & 35mm, APX25 120 & Agfa Record Rapid papers & Rodinal on their shelf, and re-ordered regularly. Always had just what I needed, I discovered why much later - they guessed my usage so ensured I could always buy what I wanted.
The late Bryan Barfoot ran Leeds in Birmingham exceedingly well and taught his staff to look after the customers, when I was involved in some exhibitions which were part of a Photo-festival Leeds gave us excellent discounts. Acouple of years later they did the same when I had alarge solo exhibition.
Leeds were a company who supported photographers first and made a profit after. Because they were so customer orientated you had no need to buy anything from one of there competitor.
Ian