I've got an older generation Aerostich Roadcrafter one-piece (circa mid 90's) with an armor kit in it.

Looking for recommendations on a rain suit.  Should I get a one-piece?  Two-piece?  Which brand/model have people used and do you recommend.

Thanks in advance for the advice

I'm really happy with my BMW branded suit, a two piece. I suspect a one piece on top of a Roadcrafter would be challenging. 

Yeah, good point about one-piece on one-piece.

Wondering if Bob's might have something like that in stock I could go try on.

They might or you could give mine a try.  I'll be wearing my Transit Suit so won't need my rain suit on this trip.

So far, KLIM gear is the only gear I've used that is fully waterproof. Jackie rides in full KLIM gear and is always prepared. I use KLIM pants with a BMW Ralley Jacket, but the jacket is only decent in light rain, it's not waterproof, I need to get out the rain cover when it's raining hard. I tried waterproofing it but it didn't do the job. Unless BMW steps up and provides a true waterproof jacket I'll be moving to a KLIM jacket next purchase. The advantage of two piece is you can take the jacket off when you stop, useful when it's warm or hot.  

Thanks for the offer Yermo, unfortunately I think I'm too short 

America.Rides.Mapsthanks for the tip, I'll see if I can get a set of KLIMs

Frog Toggs make a two piece suit for riders.  I have used it and it works well.

Frog Toggs make a two piece suit for riders.  I have used it and it works well.

Frog Toggs make a two piece suit for riders.  I have used it and it works well.

I wear Olympia Horizon rain gear (pants and jacket).  I’ve worn them for years and they’ve never failed me.  They’re lightweight, they fold to a very compact size for easy storage, and they’re inexpensive.  I’ve put them to the test during my annual cross-country trips which typically include riding through many days of heavy rain and wind.  My Olympia rain gear never leaks!  I won’t use any other rain gear.

If you just want an occasional rain suit go with the frog togs - cheap but not durable.
If you ride a lot in foul weather go with any (jacket/pants/boots/gloves) brand that uses Goretex. It breathes and keeps you dry in the worst of conditions. The other brands' 'rain-proof' liners leak.

FWIW, the original suits are supposed to be water repellent and there are supposedly options to maintain that. From the website: "MAINTAINING BREATHABLE FABRICS? After the manufacturing process that bonds a breathable/waterproof membrane to Cordura fabric, a DWR (Durable Water Repellent) chemical treatment is applied that prevents water from being absorbed into the Cordura’s fibers. If the Cordura fibers become saturated in wet conditions, the water forms a barrier causing vapor to condense on the inside surface. Over time and after extended wear, the original DWR treatment wears away and must be renewed. Periodically laundering gear with a wash-in treatment like Nikwax TX Direct®, or applying a post-wash water repellent product like Scotchgard®, Revivex® or Tectron®, will insure that water beads and runs off the fabric, and that vapor will always be able to pass through, even in wet conditions. Maintaining the DWR also helps textile gear dry faster after being in rain."