This question pops up so much, that the answer may as well be 42...
Which one? Someones tells first image is better. Tubes down/pump up.
If that's a 360mm hybrid being installed on the cpu, then example 1 is likely impossible anyway. 360mm and larger hybrids are inflexible as all heck:
-tubing too short; 400mm max on most models.
-trending psu shrouds plus HDD cages in modern chassis create clearance issues IF the tubing length issue was somehow resolved.
If this were to go on a gpu instead, example 1 would be totally possible.
240/280mm are more flexible for cpu-front-intake-tubes-down, but some chassis are too long from the front to the motherboard area that they force you to go tubes up with them anyway.
Example 2 is fine, but it makes more noise over time as the ratio of fluid to air changes, forcing you to either:
-replace it before it outlives its utility, because the noise becomes unbearable.
-move the radiator to the top of the chassis - and if that's not possible(due to either ram clearance or just size incompatibility), you'll have to replace it anyway.