EF500DG Super vs YN 468 - speedlight on the cheap

I'm currently using a Sigma EF500DG-ST which I've had forever, it's very basic but works well for on-camera flash. I'm looking to expand my horizons and experiment with off camera flash both alone and maybe in conjunction with an on-camera speedlight. So to get started I plan on getting a pair of YN-622C transceivers. For my next speedlight I'm thinking about either a used Sigma EF500DG-Super or else the YN-468. Is there anything the YN-468 will do that the Sigma can't? Am I on the right track?

The Sigma doesn't have remote manual control with the YN-622C, only TTL. You can set manual power levels directly on the flash though.

The YN-468 II has full control on the 622C, but its a very low power flash for off camera use. The cheepest good options are the YN-565EX which is full power but no HSS, and the YN-500EX which has HSS but 0.5 stops less power, both from around $145. The YN-568 has full power and HSS from around $180.

If you really want to go cheaper than those its probably better to just get a fully manual YN-560 III and RF-602 transmitter.
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