Lux has base mana of 570 at level 6, so a 0.3% regen every 5 seconds from Meditation before level 6 will be less than 1.71 mana every 5 seconds. It would take over 175 seconds (almost 3 mins) to get the 60 mana for an additional skill. The 1% more damage from Merciless will deal about 2 more damage from the simple combo of E, AA, passive, Thunderlord's at level 3. This is not a lot, but it might make the difference when you are trying to burst. After around level 12 or so, I usually don't have an issue with mana running dry before I'd back anyway to buy or heal, and by then, the 1% extra damage is going to be worth around 6 damage for the same simple combo. These numbers seem very low for both the mana and the damage, but what it really comes down to is whether or not one is more useful than the other. Extra damage will always be useful. Extra mana becomes useful only when you accumulate enough to cast a spell with it. It also comes down to preference. If you are more cautious in lane and there long enough where the extra mana will help you cast a spell, then Meditation might work. Note that I'm being a bit unfair with the mana regen here because you don't need to recover a full spell's worth for it to be useful. With a Doran's Ring, before level 6, Lux will have about 11.53 mana regen every 5 seconds. That means that it takes around 26 seconds to get 60 mana. If you cast spells averaging 60 mana, then you can cast about 7 spells before running out (453 average max mana pre-6). But the fastest you will probably ever cast 7 spells when first getting to lane is about 60 seconds. While casting those spells, you'll have regenerated 138 mana, which is enough for 2 more spells, which takes another 12 seconds or so, giving us another 27 mana. This leaves us with about 78 mana (453+138-420-120+27). That's good for 1 more skill (likely without having to wait), leaving us at around 18 mana. That's not enough anymore. If we had 1 level in Meditation, we would have gotten about 22 mana (in 72 seconds). That would bump it to 40 (not enough for a skill)). Now, this is considering the fastest we can cast spells. Likely we are not, so 1 level in Meditation likely allows us to cast that 1 additional spell when we are ready to. Then it's probably worth it. But that's assuming that we are in lane to cast 11 spells before backing. In bot lane, that might be the case. Mid, maybe not. I'll have to try it bot lane.