Hondata's pricing structure is set up so that you can either buy just the ECU and have a shop tune it for you, or you can buy all the equipment needed to tune the thing and do it yourself. Either way you're going to need a dyno to tune the thing. As long as you're sort of close to a shop that has the equipment to tune the Hondata and you're not planning on tweaking it yourself, you can just skip buying the extra stuff.

As for the injectors I always get the two mixed up. Basically the difference is in impedance. Saturated are high impedance and peak/hold are low impedance. Hondas actually need need a high impedance injector. Older Hondas use peak/hold (low impedance) with a resistor pack. Hondas from '92 or newer use saturated (high impedance) with no resistor pack. You can run peak/hold on a '92-up Honda with a resistor pack from an older car but there's no point unless you are trying to run the 450 cc/min injectors from a turbo DSM which just so happen to be peak/hold. So yeah if you're buying brand new injectors, you want saturated ones.