I'm not in UK, but I try to support my local photo store, which has gone almost entirely Ilford, so that leaves me using Ilfosol 3 developer and Ilford Rapid Fixer. Ilfosol seems to do horribly on almost nothing, and brilliantly on almost nothing -- in short, a general purpose developer with which you can't go too wrong, but I've never heard of anyone raving about it and becoming a dedicated partisan of it (as happens with Rodinal, Perceptol, etc.). I process very few rolls, so Ilfosol being a liquid concentrate helps there. (I've read -- though sceptically -- that mixing a tiny fraction of powder from, say, a D-76 bag that's meant to make 5 gallons or similar, risks having not all the chemical components in the 'sample' of powder that you take.)
I find HP5 has intolerably obtrusive grain in Ilfosol 3 (yes, even in their own developer, not only in Rodinal as mentioned above), and so have basically gone off HP5 entirely, in favor of Delta 400 and TMax.
+1 to newdorf's comment: Staying with one brand for film, dev, and fixer is not needed. I've used Ilfosol 3 on Ilford films, Kodak TMax, Fuji Neopan 400, and even Efke 25; this last is very weird, finicky film. It works, as I said, satisfactorily but never excitingly, on all of them. If you seek exhaustive manufacturer instructions, well of course the Ilfosol documentation gives the most detailed suite of standard, push, and pull developing times for Ilford's own films. But that's not a reason to match Ilford with Ilford, since the massive dev chart documents every imaginable combination.
--Dave