One thing to note: The benefit gained from the expansion of the chi pool provided by Ascension is hard to quantify. Brewmasters and windwalkers are typically attempting to spend chi as fast as they bring it in, so increasing the maximum doesn't benefit them much. Mistweavers do engage in some short-term chi pooling, so it's of some benefit to them, but how much really depends on your play style and skill level. As such, I'll be focusing on the 15% gains below in my analysis.
Oh, and if you're not a fan of math, you may want to skip to the end of each section.
Brewmasters like to smash things in the face, and stay alive doing it. To do so, they need chi, and to get chi, they need energy. Brewmasters get their energy from three places: baseline regen (10/sec), Stance of the Sturdy Ox (+10% regen), and haste (roughly +2.5% regen per 1000). Ascension, of course, will increase that energy regen by an additional 15%; unfortunately, you have to choose between that and Power Strikes, which gives the brewmaster 1 free chi every 20 seconds. Which is better?
Well, if you look at the situation strictly in terms of chi generation, it's no contest. At an average level of haste (2-3k), Ascension will generate enough energy to give you an extra Jab/Expel Harm once every 24-25 seconds. That's a big downgrade from Power Strikes' 1 chi every 20 seconds. Of course, there's some other considerations to consider: Ascension is going to increase your tanking DPS slightly, since you are getting extra Jabs you wouldn't get normally. Also, if you typically don't use your Power Strikes buff on cooldown, it won't be as good in practice as it is in theory.
Overall, while I'd still give Power Strikes the slight edge (especially for things like heroics where you'll have it up for each pull), Ascension is certainly a a reasonable alternative choice.
Windwalkers like to kick things in the face, so they LOVE energy. Just like brewmasters, more energy = more kicking. While they don't get the brewmasters' energy regen from their stance, they compensate by having Energizing Brew, and their stance gives them oodles of free chi.
In contrast to the other two specs, Ascension is much better for windwalkers than Power Strikes. The chi generation is fairly identical between the two, but the extra energy allows for lots of extra Jabs, which translates to an extra 2-3% DPS in theory. Unfortunately, in practice, I find Ascension to not be as strong a talent as the simulations indicate.
Why? Well, simulations assume that we're DPS'ing 100% of the time, and real raids don't act like that. The windwalker DPS spec has always been very close to being GCD capped (similar to frost DK's) and Ascension increases that tendency, to the point where you're nearly guaranteed to energy-cap during Fists of Fury, Energizing Brew, or any significant off-boss time. Ascension is good enough that I'll still recommend it (especially at lower gear levels, where the GCD capping problem isn't as significant), but it wouldn't surprise me to see things get tweaked before Tier 15, as it'll start causing the significant devaluation of haste gear.
Mistweavers like to...heal things that are hit in the face? (Abandon metaphor! Abandon metaphor!) With the increase in mana costs in the last patch, the increased mana pool provided by Ascension seems to be very appealing. How does it compare to Power Strikes, however?
Well, this comparison's a little more difficult, so let's look at Ascension first. Taking this talent provides mistweavers with two primary benefits. first, it increases your maximum mana pool from 300k to 345k (or more, if you're a gnome). Second, it boosts the amount of mana regenerated by your Mana Tea from 12k to 13.8k. Converting that to an mp5 estimate is very dependent on your healing style and how much Mana Tea you generate and use, though. If we estimate consumption at 1 stack every 10 seconds, then that results in a 900 mp5 increase. Combine the two and you have what looks to be a pretty sweet deal.
How do we value the free chi from Power Strikes in terms of mana regen, though? Spleener on the EJ forums had the simplest explanation I've seen: 1 free chi is equal to the cost of your chi generator (Jab, for example) plus a quarter-stack of mana tea, since you'll be quickly consuming that free chi and generating tea stacks. With Jab at 11.8k mana (The 30% hotfix to increase mana costs isn't currently reflected in tooltips, by the way) and a quarter-stack of mana tea adding an extra 3k, you get 14.8k mana returned every 20 seconds, which translates to a 3,700 mp5 increase. That's...quite a bit better than the regen from Ascension. Even if we double the estimated mana tea consumption rate above to 2 stacks every 10 seconds (which is the maximum you can get with glyphed mana tea), the talent is still only half as effective for regen purposes as Power Strikes.
Regen isn't everything, of course; having that extra 45k mana to burn through really helps, especially on shorter fights where you don't need to worry about conservation as much. Therefore, while I'll still stick with my general recommendation of Power Strikes for raids, feel free to try Ascension for fights that are 2-3 minutes or less, such as your average 5-man boss.
Summing up, I think my off-the-cuff evaluation was more or less correct: Two of the three monk specs can use Ascension, but it won't be their first choice. Only windwalkers should immediately consider switching talents, and that's only for raids; for simply questing, Power Strikes is a much better choice. Until next time, keep on kicking!
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