My favorites are HP5 and Delta 1000 (PLEASE change the name of this product, Simon)! I develop them both in Ilfotec HC, and sometimes in Kodak D-19. Is there an Ilford version of D-19? If so, I would use it instead.
They give me fast shutter speeds and deep depth of field in good light. I sometimes shoot while moving, or from a car, and I often zone focus, infinity focus, or guess focus. These films help a lot. I don't know how people did it in the days when a 100 speed film was blazingly fast. We are living in the lap of luxury with HP5 and Delta 1000! Between the two of them, I can work in almost any lighting condition hand held. I love their tonality and their maleability (but that is high speed films in general). I just love the flexibility and versatility of high-speed films, not to mention their look. Delta 3200 is also a great film for taming high contrast. I love its "washed-over"-looking grain pattern for a lot of things, as opposed to the gnarly, clumpy grain you get from a random grain film. Oh, yeah. Let's not forget the fact that I routinely use this film with two and three stop pushes, and it looks great. That is without even breaking out the D-19. My usual development (I won't use the word "normal" to avoid confusion with zone system applications )for this film is 15 minutes in HC 1:31 (what Kodak calls HC-110 dil. B) at 68F, and I use time-temp chart to adjust.
I used to use Kodak everything. Tri-X 320 was my favorite in medium in large formats, and 400 in 35mm. I never liked T-Max 3200, though. I just used pushed Fujicolor 800 and 1600 for really high speed shooting. I used D-76, HC-110, and D-19. Now I support Ilford because they have come out and blatantly stated what they are trying to do for film photography. I haven't heard shit from Kodak. Just the introduction of stupid and unnecessary new films while they constantly axe the old favorites that I loved, and on which I often relied. Once I made the switch, I realized that I like Ilford's overall line of products better than Kodak's. Their chemicals are convenient to use. I love syrupy concentrates so I don't have to monkey with powders. I love that their fixers are non hardening off the shelf in liquid form. I just wish they were not English, but United Statesian.
p) Well, at least I am helping to give some English bloke a factory job, plus all the people responsible for getting the stuff across the pond to Freestyle and Samy's. I go to Kodak for C-41 chemicals, their wonderful Endura enlarging paper, which I like way better than Fuji's, even though they have discontinued all but Supra, and very occasionally some color film in small or medium format, but I mostly use Fuji. I do use their 400NC in 4x5, however, as it is the world's only color 400 sheet film as far as I know. There are a few things I dislike about Ilford. I do not like their bottles, as the factory seal never comes off cleanly, thus the lid never forms a tight seal once you have removed the factory seal. I love Kodak bottles, and never throw them away. The seals come off no problem. I have them many years old and just keep reusing them. I also find Kodak's data sheets incredibly more informative. I wish Ilford would publish some more detailed data sheets. Take a hint from Kodak's, for instance, with detailed curves for various developers, times, and developing methods. More information!!! Hell, why not write textbooks and market them to schools, along with a complete analog photo solution? Chemicals, paper, film, textbooks (from basic to very technical), partner with equipment makers to help set up state of the art school darkrooms.......now I am rambling.