Another difference that could be a consideration is that the DI on the id14 is 500k while on the id22 and id44 is 1meg, which IMO is a pretty significant difference for an instrument DI. If instrument DI is important, I think it could be worth a bit more to get the id22. I had the id14 for awhile before even consider input impedance, and thought the DI sounded dull when using amp sims, and was getting much better signal when going through modelers with everything bypassed, using the same plugins. It was because of that lower than typical 500k on the id14.