FFF
As a 200-hour PPL, I consider myself "substandard" compared to the guys who fly in/out of LHR every day. That's one reason why I wouldn't go to LHR.
200 hours? Don't put yourself down, you should be perfectly capable of going into LHR. If they bring you in via downwind or base, just keep a tight circuit. If they bring you in via final keep the speed up. Make sure you get it on the ground quickly when tower tells you to and get off the runway pronto. It's just like any other airport, even easier really as the runways are harder to miss. Hang on you are talking about LHR, I must be thinking about taking little planes into far busier airports
I've flown in light aircraft with heavy-iron skippers who were positively dangerous. I remember being with an Airbus captain in his cub when he had to go around at approx 6000ft and 90 degrees F. Idiot forgot to retract flaps, scared the cr@p out of me, apparently his plane does that automatically.
Hours count, but it's also all about how much you have flown that type recently. NPPL pilots could easily be more proficient than your PPL, CPL or even the almighty ATPL.
I still cannot see the point of the NPPL though, look at the take up on the recreational pilot certificate in the US. It's pretty negligible - but then PPL medical standards are more practical in the US. Why should somebody with a medical condition which is deemed too unsafe for them to fly a warrior over my head with a PPL piece of paper in their pocket, be safe to fly the same plane over my head with a similar piece of paper in their pocket, except it has an extra letter on it???