Yep - RIC took all of the comments onboard and released the 4004, which addressed them.
Guess what? Everybody still went and bought the 4003!
The reason RIC still make the 4003 is because that's what people want to buy.
Me, I like the way they play, the dual truss rods (which work as described), the bridge/tailpiece (I've tried the others and put back the stock one), the incremental design tweaks, the quality of the finish (I picked up a Ric pickguard on the weekend and could tell immediately it was an original).
It's a 60 year-old design which is still the best on the market.