Ok I am putting together a mid length build and I am looking for a rail system that will work with a FSB attached on the barrel and still has a little bit of rail space in front of the FSB. I see DD only makes the 9.5 FSP rail and only goes around the side of the FSB and I am not really sure about the Troy rails and I am have looking at the Centurion rails and they only seem to make one that goes around the side of the FSB. Who makes a rail like the DD RIS II FSP rail but for a mid length barrel?

The next question is about ambi mag release. I have looked at the Norgon, Troy and KAC. From what I gather the Norgon is good but tends to be hard to activate, the Troy tends to sit against the lover and you get wear on the lover from it. I have not really been able to find that much out on the KAC except that it is a little strange due to the way it sits and being a little longer and might get in your way or caught up on something. Any of you guys prefer one over the other or which one would the hive recommend over the other.

The Norgon release is nice. It take a bit more poundage releasing a full mag. Nothing to strain over, just be deliberate about the operation.

I have the Troy release. This is because I also use Magpul BAD levers, and they stay out of the way of those. I don't worry about finish wear.

I also used to have a Troy two piece FSB cut out rail, but it doesn't sound like you are interested in those, so I'll save that bit.

I am looking at all for the ambi mag releases so I have not stopped my choice of options.

The rails are in the same boat as I am looking at of the options available to me. I do want to be able to mount my light as far forward as I can with out to much barrel shadow.

If you aren't using an extended bolt catch then all options are available to you. If you are, you may want to consider the Troy mag release, just because it plays nicer with the extended bolt catches - space sharing wise.

Where the Troy rail is concerned, having a mid length means you'd be limited to their slick rail, no quad rail is offered for mids I don't believe. However, if you are stuck using the standard delta ring assy., this rail offers a reasonably priced, easy to install option. The only thing I had to do was remove the sling swivel, which is way better than dealing with taper pins on the FSB, IMO.

That said, I have loved every DD rail I've ever owned. Top notch.

ETA: looks like Samson also makes a mid cut out rail.

Ok thanks I will check out Samson rails and see what they have.