I have a 2009 LWB GLX done 50 000km (just serviced). To extend Maintenance plan 2 years/40 000km (includes warranty) is R31k plus R4k for next service because its a Cambelt service. To extend Service plan (no wearing parts) is R8k plus R4k.
The car has been 100% reliable to date and just finished a fairly punishing 4000km Kalahari trip.
I only do about 15 000km per year so what advice out there? As a new Pajero owner I don't know how reliable they are or what services cost as they get older...?
1. Full maintenance ?
2. Service plan only ?
3. Service plan plus separate warranty (R10k) ?
4. Nothing - service through dealer or go private.
R12k for a service plan over two years or 40k kms, and you do no more than 15k a year.....means that you will probably get three services out of it before it expires at the end of the two years, at an average cost of R4k per service. I also, like you, do very low mileage...the vehicle is used for weekends and long trips only. So I would not even begin to consider that offer.....my vehicle is going straight to an independent service agent at the end of its service plan - but then again that's just me.... 
I have yet to see a "warranty" claim fault submitted to the forum. Head gaskets seem to go on the 250 - 300k mark. As long as the timing chain is replaced when due, you should have all the reliability in the world. The only problem I have had is the head gasket on my 2002 going on the 300k mark. My 2008 is on 115k now and zero problems so far.
If you can feel the grass between your toe's, your flying too low!
3.5 GLS F/LIF 1998 Lost to the x wife
3200 Tdi GSL 2001 Written off
3200 Di-D 5Dr A/T 2002 338 000 Sold
3500i A/T 5Dr 2001 Sold
3.2 Di-Dc GLS A/T 2008
3.5 GLS F/LIF 1998 Lost to the x wife
3200 Tdi GSL 2001 Written off
3200 Di-D 5Dr A/T 2002 338 000 Sold
3500i A/T 5Dr 2001 Sold
3.2 Di-Dc GLS A/T 2008