Powdered chemicals last for years in storage - a big advantage. Ilfosol seems prone to sudden death in the bottle after a time.

1-litre packages of D-76/ID-11 will do you about 6 rolls of 135-36 or 4 rolls of 120 assuming you dilute 1:1, so it isn't hard to get through it fast.

Alternatively you can get XTOL, which although powdered, can be mixed at 20 C and used immediately. However, the smallest package is 5 litres.

I find mixing D-76 a couple of hours or so before you need to actually develop is good enough.