So I finally got around to testing out all second generation flasks and realised how truly bad some of them are, though I did find a new love. Here are my personal opinions on the less tested second gen flasks as well as some of the data I got on them. Since it is just my numbers they have a very real possibility of being wrong so just a warning beforehand (would love some counter data here if possible), could not find others testing numbers so nothing to go against.
Vampiric Vial, rather weak but not terrible if you kill a ton of enemies. The chance to get a vial back is rather low though at around 10% so if you can not get at least 10 enemies within the buff timers you are at a loss. Problem is that while the flask is fine alone if it is compared to Valorous it is severally lacking since it is 5% chance to get a flask on hit is better than 10% chance on kill.
Quester's Vial, perfectly fine if you overleveled and clear a couple dungeons without using flasks. The chance for this one is 20% since I can often get a proc per five dungeons. I question the usefulness of this flask since you will almost always use one in a single dungeon. Even Vampiric, which is worse than Valorous, is better than this flask designed for dungeon clearing.
Conjurer's Crucible Vial, possible the worst of all chance flasks. The chance to trigger is somewhere between 20% to 25% and considering that mf builds have around 20% chance to trigger per item you are looking at an overall 4-5%. Valorous, Vampiric, and even Quester have higher chances per dungeon to get flasks back.
Just going to stop here for a second and put out an idea. What would anyone think if Conjurer and Quester got changed to 100%. That is a reliable 1:1 for Quester but if you use more than one you are at a loss, so it is excellent for dungeon clearing while terrible for anything else. For Conjurer it has the possibility of high flask draw but requires mf gear, drops, and good rng instead of being bad even on mf gear.
Vial of Minion Multiplication, pretty fun to play around while also being one of the most bugged flasks. It says it doubles emblem minion spawns, which it does, but because of what can only be described as a bug you can get triple the minions. After using the flask once use it again, it will only despawn a pair of minions instead of all of them while summoning the next group. While this is a bug it would be interesting to keep it as a feature, using two flasks for triple minions for higher burst. The other bug is that if you summon any melee minions one of them will see you as an enemy, not so great since it makes that minion useless.
Vanguard Vial, the more expensive but weaker brother of Chaos. Its description says you get a random emblem effect when first hit in combat but this is not entirely true. What really happens is that when you are hit you get a random effect much like Chaos but then the ability goes on cooldown for 30 seconds. This just means every 30 seconds you get a random emblem effect, good in both short fights and long ones but you have less control when compared to Chaos (never thought I would say Chaos has control).
Evasive Vial, the description is incorrect but that also makes it equal to or greater than the most expensive flask. The description is pretty close to Chaos or Vanguard but the effect is not that, instead it is almost a complete copy of Unleashed Power. Every time you dodge there is about a 25% chance (sometimes feels like 33%) to use your flask and both your emblems without consuming a charge (will consume if your flask count is full). This is insane if you really thing about it, Unleashed Power gives up flask count completely and costs over double while Evasive has a flask count and higher chances for free flasks. You can dodge every 3 seconds while most ultimates are 40 seconds, so even with it not being a guaranteed proc you get more in the end as long as you dodge once every 10s or so. I have not picked this up until now because of the description but now that I know how it really works I can not contain my love for it.
So there we go, finally got that out of the way, thoughts? I can understand that the chance vials are less expensive and thus suppose to be a bit weaker than the other second gen but they don't even compare among themselves. On the other hand Evasive is strong for its price, you get a normal 40%/8 flask but with the ability of Unleashed. Second gen doesn't seem that there is a middle ground, either really strong or don't bother using.
My advice is try it out on PTS first to see if you like it, saves resources if you find it does not satisfy your playstyle. I don't use condensing myself but just knowing how the two flasks work I would put Evasive ahead. Condensing is 50%*7 with a flask every 45 seconds while Evasive is 40%*8 with a 25% chance to use a charge while dodging, little difference in health and count so only the effect really matters. In the time it takes for you to get a flask back you could dodge 15 times, if you want a flask in the same amount of time you would need to dodge only every 11 seconds. It is more rng based but the chances are not bad and there is little time take to dodge. Again, best to try it out yourself on PTS just to be sure.