Recoil and the Gun Kata Gun, Cannon Companion doesn't list IGV Options

[DrJest]

In the wake of the AVS thread below, I decided to delve into my barely-touched copy of the Cannon Companion and create a race gun designed for the aforementioned Gun Kata physad. What I have so far is:

Base Heavy Pistol frame
Heavy Barrel (1pt recoil comp, +25 dpv, -0.25 fcu, +0.5 wgt)
Recoil Comp 1 (+70 DPV, -0.5 FCU,)
Firing Mode SA/BF (+100 DPV, -1 FCU, +0.5 wgt)
Improved FCU +1.0 (+40 DPV, +1 FCU)
Melee Hardening (+15 DPV, -0.5 FCU, +0.25 wgt)

Totals at this point: DPV 400, FCU 0.75 remaining, Wgt 4.0

Moving on to the customisation section, I then add:

Personalised Grip (1pt recoil comp, +25 DP)
Extended Clip +5 (+10 DP)

Now I stutter. What I want to do is add an IGV-II, an old fave-rave for many years. That would take the total recoil compensation to 5; add another 1 for strength 5+ (do I have that right?) and that handles 2 bursts per phase without recoil. Expensive in bullets, but capable of laying down some serious fire cover if needed (bearing in mind here that the redesigned physad in question is a phys magician, has Ambi-8 and the Enhance Aim spell on a sustaining focus, which I think I have right is the replacement for spell locks). Now, in theory I think I could add the IGV-II for the nuyen cost divided by 5 (110) in DP with the weight increase of +0.25, but what FCU? There's no conceal reduction for the IGV-II, compared to the -1 for the standard; comparing their weights and extrapolating that to the FCU, that would bring the IGV-II in at half the FCU, or 0.25. Does that sound reasonable?