Whatever you use, make sure you know how to sharpen them.
Even a cheap chisel works really well while it's sharp, even if ergonomics and edge retention may be a bit lacking... Though, getting them sharp can be a lot of work as they often need quite a lot of grinding to get the backs flat.
I'd recommend getting some diamond stones and a strop... Maybe a #400 / #1000 grit diamond stone, and just a piece of old leather glued to a flat board and loaded with green compound. That will get you started, and depending on your needs, might be all you require. In time you might find you like oil or waterstones... Or if you really only occasionally use your chisels, you can just make do with sandpaper and a flat surface.
As for what chisels to get, I'll throw my hat in for the Stanley 750 Sweetheart chisels as well. I've used both the Stanley's and Narex chisels (though not the Richter line!). Narex Chisels are also good. You should consider whether you want socket chisels or not. I like them for their strength and repairability, but you should take care because occasionally, the chisel handle will pop off which can lead to accidents. As steel is concerned, I recommend avoiding A2 -- it's too prone to chipping and doesn't take and hold an ultra fine edge all that well IMO. It's quite a bit harder to sharpen than many other steels and imparts little benefit.