Landrover defender 90, 300 tdi wheels/tyres

Hello,
Ive just bought a 1997 DEFENDER 90 which has 15" wheels with Kingpin radials 31/10.5/R15 tyres on. I know these are not standard by any means but will the road handling/ suspension and tracking issues etc be effected.All appears OK with good clearance and turning circle. It is worrying me about the 15 rather than 16 inch rim size!!!! Bought from a dealer and the tyres are nearly new so they have been used. No other mods at all been done on the vehicle. Absolutely bog standard.
Help and advice please.
PS: If this is in the wrong area for discussion, then I apolgize now....
thanks
Rob.

Is there any stress on the re-uptake inhibitors?

31,10.5,15 are fine dont worry

Thanks for the "straight talking" advice stu, some of the "responses" were strange to say the least but it takes all sorts eh, again appreciated.
Rob