I'd first of all recommend the powder through expander from powderfunnels.com, and then get the PTX quick change linkage from Midway:
You can then save a station on your press, and get a separate linkage for each caliber, and keep it with those dies - no need to adjust for expansion for each caliber.
You can then use a single resizing die for 9mm & .380, and then either use a single seating/crimp die for both calibers, and adjust it each time, or get a die for each caliber, set and forget the dies for each caliber.
After researching and doing the math, I ended up getting the powderfunnels.com PTX, a linkage for each caliber, and a die set for each caliber, using the Hornady New Dimension dies.
My rationale was as follows: If you buy 2 dies separately, it was more than the 3 - die set. My Lee dies were too short to adjust well in the LNL AP. The Hornady seating / taper crimp die saved a station so I could add a bullet feeder later, and use a powder check die at the same time. I like the alignment sleeve in their seating/crimp die - good especially if you get a bullet feeder later.
I personally want to set each set of dies up one time per caliber, use a separate powder metering insert per caliber, and PTX linkage per caliber, that way caliber changes are nearly automatic.
I also invested in a second powder measure and case activated linkage for rifle, so I wouldn't have to change out the rotor drum when switching to rifle.
In the long run, it did cost more, but to me the efficiency and exactness of changeovers is key.