96 940 ODB2 equipment

I have a 96 UK 940 Turbo and was considering buying a ODB2 interface and
software for laptop since it has the socket and the Volvoclub website
confirms it has ODB2.

The car currently has a fault whereby it stalls after acceleration
(seems to be not actuating the idle valve) if you put the clutch in,
although there is no check-engine light (I can't see one on the dash).
If you hold the accelerator above tickover for a few seconds or
decelerate slowly while in gear it is then ok and will tick over as normal.

Google shows Vital-Engineering has a bluetooth/RS232 unit and available
by Euro Car Parts, but I heard bad reports about it, but nothing
specific as yet. The web site only says 'from £84' and advertises
online ordering but requires email.

The only other PC unit I have seen is the ELMScanmaster 5 Package, but
costs £200 and doesn't say what it does clearly so I can't compare
functionality.

Anyone any suggestions good experiences with ODB2 stuff on the 940?