Both options mentioned are very good but personally I would wait for the results of Peters testing in the thread mentioned by Dillen before making a final decision as both options are relatively expensive.
Plus points for sound-smith cartridges are that they are built new from scratch (I own one and am extremely happy with it) and come with a 12 month warranty. The only slight downside for me is they aren't quite as refined as the originals eg:- the lack of a styus guard & the info being printed on a sticker and applied spring to mind. There is also the price of these for anyone living outside of the USA as they are subject to import duties which are quite hefty in the UK.
Plus points for the rebuilds are that they maintain the original shell and simply look better but I could not comment on the sound reproduction as I haven't used this service myself. Also a cheaper option for EU members - obviously import duties would again apply for coutries outside of the EU.
Either way both options are preferable to buying a used or "new old stock" item as the suspension will have hardened on ALL of these over the years and could fail at any time without warning. They also tend to sell for as much as - or somtimes more than a new soundsmith or cartridge rebuild.
Chris.
The use of metaphors should be avoided like the plague. They're like a red rag to a bull to me.