They've worked well for me. They can be a little troublesome when new, when the ALS mechanism has a sharp corner that snags the slide cutouts. However, this works itself out with a little break-in, or you can remove the ALS mechanism and round the corner slightly with a file to hasten the process.
The older suede lined ALS holsters (6000-series) also have less clearance around the light rail on the M9A1/LTT guns compared to the newer unlined 7000-series. This can restrict the draw path so that the gun doesn't quite fully clear the ALS mechanism on the way out. I have one 6378 that works well with my M9A1/LTT-framed guns, and one that doesn't but is just fine with non-railed frames. I've been meaning to remove some of the suede liner from the tighter one to see if that fixes it, but the easy answer IMHO is just to buy the 7000-series if you have a railed frame. FWIW, the 7000-series even works with a Brig Tac.
Yes. It's tight, but the PX4 compact will work in a full size ALS. I removed a little bit of the suede liner near the rear sight, and I think I may have lightly heat gunned the holster body near the forward portion of the slide to gain just a little more clearance. May be one of those things where it depends on which side of the tolerance scale your particular holster falls, but with those adjustments mine works well.Will the PX4 compact fit PX4 full size holsters? They make an ALS for the full size, but I don’t know if they have an RDO option.
This is all for iron sight guns. No Safariland duty options exist for RDO Berettas, as far as I'm aware. It looks to me like you could cut away some of the holster body on an SLS, but I'm not sure how much clearance you'd have for the optic once the hood is rotated forward...and I've never looked to see if there was ever an SLS option for the PX4.
The black sharpie lines show the area where I removed the suede on this PX4 FS holster.