Boomer I bought the same regulator/filter last month, it's the Paasche Ra75, and IMHO is well worth the money.
I could have used a standard reg. but the graduations on the gauge would have been too great to allow accurate control at low pressures, ie below 10PSi. This one has graduations at 1PSi increments as it is designed for use with A/Bs rather than air tools which operate at far higher pressures.
I've been playing with mine over the last week or so, and it makes a huge difference to what you can achieve with an A/B.
Karl