Cheers for the warm welcome lads and lasses.
Yes, Have to agree with the dilution rates as mentioned. 10-1 for the engine bay is more than strong enough for a clean engine bay. I tend to just spraying it on the non mechanical areas though.
I use another bottle with plain old water in to spray rinse the areas g101 was on after agitation. So I don't go spraying it everywhere in the engine bay. Little bit at a time avoiding all the electrics and so on.
On wheel archs etc... I would go for a 5-1 dilution for a bit more cleaning action to get tough stuff off.