It's unfortunate that the 'Ricky' hate clouds the debate.....understandable on the basis of the objectionable owner but if we compare just the basses and not their 'baggage'. However, I think these 2 basses are very different animals coming from different design points and eras. I've played both and for my sins still have a Rick. Ergonomically they both have flaws, I don't like the bridge pup cover on a Rick (and the fact you have to fill the hole when you take it off) and I don't like the fact that the 1st fret feels a mile away (to me) on the Spector. I can't comment on quality, I've only had 2 Ricks (my current 4003 and a previous 4004Cii) and both are/were top notch build but I understand others have had different experiences. On a bass at this price level though I'd never trust to luck and would always play before buying.
On the sound side, they are very different, I agree the Spector has more flexibility but they are far more flexible than most basses conceived in the 50s/60s. The 4003 is fairly flexible, at least as good in this respect as a Jazz and it has THAT sound as Cetera has previously said.
Price wise I think anything from the US is overpriced at the minute - the £/$ doesn't help here. But in terms of the Rick not being worth it.....only the OP can decide that, FWIW I wouldn't pay over £2k for one but I wouldn't pay over £2k for any bass.