For me, since I have a couple of challenges enabled, the warrior seal, which can carry over a single +1 armor upgrade, as well as an enchantment once you get the talent, provide more consistent win rates for the warrior than the duelist. The extra armor especially helps in the early game.

Beating the game is not a sprint but a marathon that requires endurance. The best offense is a good defense and it's particularly true here. You're better off prioritizing having enough armor before you invest in your weapon. I play with reduced scrolls of upgrade but I'll prioritize having +7 scale or plate armor before DM-300. In some cases I'll spend a scroll or two on leather or scale armor to ensure I don't lose a run. That's at the cost of upgrading my weapon later. You can beat the game with a +2 or +3 weapon but it will be harder if you have poor armor.

The shops will always have at least one scroll of identify, remove curse, and magic map. If I don't have a stone of intuition on hand, I like to convert a scroll of identify to 2 intuition so I can find out which is the remove curse. If there's a few other scrolls at the shop, you can end up using more than one scroll's worth of intuition stones but generally you're conserving cost. I typically employ intuition for identitying which is a potion of strength and which are upgrade scrolls in the early game. As well as which potions are which for rooms that require specific ones. I generally try to use the stones sparingly as resources van be sparse in the early game.

Btw the 'buff' that duelist got in that update is really far more of a rework. 1 energy refund instead of 50% refund is a 60% increase in the 5 cost ability which is huge. Frankly id say that for people who knew how to abuse monk last patch, its actually a huge nerf

Contrary to what everyone so far has said, I think the duelist has always been better than the warrior. The weapon abilities are strong and varied, and have only gotten stronger in recent patches. The abilities can get you out of so many jams, especially the shield one or the dirk one. And the abilities that daze your enemy (hammers, axe) or increase your attack speed and accuracy (scimitar) make combat so one-sided.

You don't need armor if you kill everything in a couple turns with a high level weapon and guaranteed hits. I have ascended so many times with just +4 scale armor.

I usually play Champion, but sometimes Monk if I get a good wand early. I've definitely abused the hell out of using Round Shield for invulnerability coupled with Meditate. You're immune to all attacks while meditating and then you heal and get wand recharging. I guess that got nerfed though, by not giving back as much energy now.

The bug has already been fixed, I saw it on the changelog. I play every single run I intend to win with the warrior (at least 30, give or take), and I've actually won little games with the duelist (like 2, if even that) . I just focus a lot more on armor, I like armor focused playstyle. And warrior's the best for that. I guess that's why I prefer warrior. Funny story: When Evan made it so warrior's talent of identifying weapons and armor got nerfed to only armor because of the duelist having the weapons focus and all of that, I got angry at the duelist because it seemed too weak and now even stealing the best talent from my favourite character (almost literally, because it took it away from the warrior), dunno, I don't use her.

The warrior is designed to be the simplest class. It’s meant for beginners to help ease them into the games mechanics and pretentiously go for a first win with no challenges enabled.

Duelist is the most advanced class. She’s designed for experienced players, especially who like to play with lots of challenges on. She’s extremely powerful but complicated to play, so it’s a tradeoff. However, she may now be the easiest class for getting your first 9 challenge win.

Think of the duelist as a melee wand user (with weapons as wands) and you've got a better read on the class before specialization. The warrior is the tanky physical class, the duelist is the bursty offensive class.