Uwe, I have read on other forums of at least a few other people with 4003s8's with the exact same problem. But, there are also many owners with no issues at all.
Since my 87 was in almost mint condition when I got it in or around 2001, (and I got it from a local, small, vintage music store), there is the possibility that it was sent back to rick by the original owner and they did the mods. Or, maybe it didn't develope the bow until after the warrenty had expired.
I asked John Hall once about the imbedded bridge assembly and he replied that that did not sound like anything that they would have done at the factory. But, I recently read somewhere that some of the model 4008's were shipped from the factory with the lowered (imbedded) bridge assembly. I have never seen a close up picture of one, and I can't remember where I read that...maybe the rick forum. Whomever did the bridge rout on my bass did a very clean job and if you didn't look closely you'd never know that it's not stock.
I agree that rick certainly should have done more research before sending these out...perhaps a wider/thicker neck, larger rods, graphite re-inforcement and an 8 saddle bridge would not have been too terribly hard to implement.
I am really happy with the results and even though I play in a blues band these days I still think I'll take it to a rehersal just to hear it with a full band.
The last time I played it live was with an Americana/rock band and we had my rick 4003s8, a Burns double 6 electric guitar, an electrified/acoustic slide mandoline, and a jerry jones electric sitar! There were a LOT of strings on stage that night!!! cheers, David