Delta 400 may be less finicky than TMax but it is still a bit prone to block up in the highlight areas, I find, despite great care in my developing.(posted 8830 days ago)TriX is very nice but HP5+ has a finer and more pleasing grain structure and it is my current favorite.
I used Neopan 400 for a year but felt it to be flat and lifeless.
This is all represented in the exposure curves, I'm sure, but I don't have any feel for how the curve translates into what I like to see on paper, so it's cut and try.
My current development scheme: HP5+ @ EI 200 developed in PMK @ 70F for 8 minutes 0 sec. I use a condenser enlarger. For a diffuse light source in an enlarger I imagine you would need longer development times.