I'm still using old stock from Choice Stationary. They are branded 'inkyJet' in a yellow carton andare very good. The new types sold by Choice are claimed to hold 30% more ink but pro rata are much more expensive.
I looked around for alternative suppliers and came across
They sell the same 'inkyJet' carts but at less than £1 per cart! When I need replacements again I intend to give them a try.