So, I'm going to start this review by pointing out that I'm becoming increasingly prejudiced towards Abandoned Arts products. Their Spell-less Ranger Archetypes are some of my favorite and they have a wide array of products that are both fun and balanced.
Now, to the meat of the thing-
The .pdf is well written and edited (something I have come to expect of them) and laid out in the concise two-column parchment format in which all of their supplements appear.
Class Acts: Monks features 6 new Style feats and the associated feats to build off of them. Many of these feats are fairly pre-req heavy, but to me this is honestly not much of a downside. I think that a monk taking the pre-reqs to build towards these feats really will feel like a martial artist developing a "style" and all of the requisites are fairly achievable for a monk or fighter, though maybe a bit of a stretch for most other classes.
The hydra style leads to a fairly powerful capstone feat that allows a monk to make a full attack as a standard action under a fairly specific set of circumstances, a cool ability that may allow a monk to utilize both their enhanced mobility and their Flurry in a single round. I'll have to play with it a bit before I'm willing to commit to deciding whether this a much-needed enhancement to a class with singularly disparate abilities or an OP addition that pushes the characters power a bit too far.
All in all though, a lot of great tools for some unique monks and creative combatants.

This pdf is 5 pages long, 1 page front cover, 1 page SRD, leaving 3 pages of content for the monk, so let's check out the 18 new feats herein!

This pdf includes essentially provides us with 6 different mini-feat trees based on a respective new style, with the eel-style being the first among them. The basic-style feat allows you to charge in a non-straight line, granting you a bonus to AC and also allowing you to change your unarmed attacks to dealing slashing or piercing damage. The style's feats allow you an improved feinting capability during charges and also at the ability to hit a designated foe that is not the target of the charge as you pass by said foe, though the pdf fails to specify whether this attack is a secondary attack (at -5) or at full BAB.

The second style we're introduced is the falcon style, which uses an interesting mechanic - when provoking AoOs by moving through a foe's threatened area, a practitioner of this style may use unarmed strikes with power attack sans the penalty to atk until your next turn. Falcon Glide allows you to extend these benefits against all foes you passed and the falcon's flurry allows you to make a special combat maneuver against a foe that threatened you via an afore-mentioned AoO to temporarily blind a foe and dazzle them even if they withstand your assault. The Griffon Style is especially valid for monks capable of flight, allowing you to make even more devastating death from above attacks, culminating in an aerial charge that can target a second subject after successfully hitting the first foe.

The Hydra Style allows you to make demoralize attempts against foes in reach sans making a full attack and allows you to make an additional attack at -2 against a foe you threaten 7 squares and finally even make a devastating full attack against such a foe as a standard action - which is woefully overpowered in my book. The Manticore style allows you to throw sianghams as ranged weapons with an increment of 15 ft. and to deliver stunning attacks via them, stacking bonuses with Hammer the Gap. The follow-up-feats allow you to embed sianghams in the flesh of your foes as a full attack, sickening said foe and even deal additional damage equal to the number of sianghams embedded in the flesh of your foes via your unarmed strikes. Cool style with an interesting mechanic. The final style is the wolf style, which allows you to make a damaging trip as a standard action (dealing str-modifier damage as a kind of representation of falling hard) and gain a bonus to grappling foes you pin after sending them to the floor as well as an increased stunning DC against foes you pinned.

Conclusion:
Editing and formatting are very good, I didn't notice any significant glitches. Layout adheres to Abandoned Art's parchment-background and 2-column standard and the pdf has no bookmarks, nor needs it any at this length. The styles introduced herein are generally well-made, though very specific in the benefits tehy grant. The ideas of the aerial griffon style and the manticore's embedding mechanics are rather neat and something I wished had been explored more. The Hydra Style's option to gain access to a feat that allows you to make a full attack as a standard action, even with its restrictions, is over-powered and needs some nerfing in my book, while the Manticore style e.g. could use a slight increase in power. The majority of the pdf's content can be considered well-made, though. In the end, this is an ok, though not stellar offering with some neat styles and my final verdict will thus be 3.5 stars, rounded down to 3 for the purpose of this platform.

Endzeitgeist out.