56k or gprs modem

Hi

I want to use a modem to receive SMS to my computer.

Models on sale appear to be:

Older type (56k i think)
Newer GPRS.

Is there any advantage in purchasing a GPRS model?

Note - I have no requirement for outgoing sms or data over gprs.

Some PCcard (PCMCIA) modems seem to be very cheap on ebay, Apart from
the requirement for a PC Card slot on the computer and the lack of an
external modem is there any disadvantage in this type of modem?

The siemens MC35 modem uses a 9 pin serial cable (a mouse cable), but
where is this connected on a modern computer which does not have a 9
pin mouse socket? Do I need a 9 pin serial card?

Thanks ColinK