My advice is to not play sabre/pistol combo because it's bad.
For primary melee, yes - but it sure looks great.
I've found exactly one combo where it shines, and that is ranged chanter with the singing scimitar (upgraded for party action speed bonus) in one hand and a good pistol in the other (e.g. Scordeo's trophy upgraded for action speed bonus to both melee and ranged). Not the greatest personal ranged damage, of course, but that's not the point there - extremely fast actions for the chanter and boosting the reactions and damage of the rest of the party via improved action speed is.
Anyhow, that's not the OPs question. Rule of cool beats minmaxing and the question is Scordeo's Edge vs Grave Calling.
With regards to Scordeo's Edge as a damagedealer in melee (as opposed to the benefits to swapping between melee/ranged), the duration during which the recovery bonus lasts scales with intellect and other effects that extend beneficial durations, something that has great impact on the weapon's effectiveness. The OP will know best whether his stats and available items supports taking ruthless advantage of this.
Also, unless something has changed in recent patches, it should still be possible to cheese the mechanic completely with a priest along to cast salvation of time to extend the duration substantially to hilarious effect.
Since the OP is playing inquisitor and hence probably has decent INT, Scordeo's Edge should do well either way.
Edited by pi2repsion, 09 September 2018 - 09:20 AM.