Across PvE and PvP, do the Siren and Harpy perform about the same?

[crimson crypt]

I'm interested in getting an Ochikochi (main robot) and a Siren or a Harpy (secondary robot) for extermination mode and to help out with faction dailies for PvP play.

I'm not sure whether the titan charge rate for the Siren and the Harpy are broadly similar overall, or if one of them is clearly better at that.

I'm not sure whether clearing extermination mode missions is noticeably easier with either the Siren or the Harpy, or if they perform about the same in that role.

It does seem that the Siren has an edge in PvP play in how it performs, based on reading I've done. Is that a general consensus from experienced players, or just an artefact of a small sample size?

Thank you in advance for any help you can provide.

[signal stream]

Those 2 are extremely similar and its typically not worth making one if you already have the other one lying around.

However, generally siren is better due to having a stronger reflector, lower cooldown and better support capabilities. (Slightly lower dmg but eh)