I quite enjoyed playing Vespers, but it is not for everyone. It was written in a way that elicited a kind of visceral disgust (unsurprising giving the setting is a medieval monastery in the last stages of being wiped out by the plague). The decay of scenery and the protagonist's mental state keeps you wondering what is real and what is hallucination, and the regular (and often gruesome) deaths of the few other cast members keeps a sense of suspense.
Positives:
I enjoyed a specific aspect of the game that I've seen complained about in other reviews. The prayers to the saints were the most interesting kind of puzzle to me (Spoiler - click to show) as the stained glass windows gave enough hints about what sort of scenario each saint can help you with. I found the writing properly atmospheric and terse, and the short timespan of gameplay fits the small-ish setting.
Negatives:
I was probably most disappointed by the lack of descriptions. Most rooms were fairly barren, and many of them served no real purpose during the game. Also, some aspects of gameplay can be finicky and require a bit of trial and error (for example, timing some actions perfectly) which is a quirk of some games that I'm personally not a huge fan of.
So overall, I would recommend this game with the caveat that players understand what they're getting into. I think most prospective players will be able to tell based on the reviews whether or not the game is one they'll enjoy.
This game was fun in a way that's common with some simple simulation-type games, but it wasn't typical for IF. It involved a lot of simple exploration, where speaking with different characters introduces you to new places you can visit. A lot of the game involves finding methods to earn money and simple resource management (rocket fuel). While it was enjoyable to play casually, it probably won't scratch your typical interactive fiction itch.
This is one of the most entertaining IF games I've played, period. The story isn't overly complicated but it's never boring, and while the "twist" (Spoiler - click to show)that the pig is the princess didn't take me long to figure out, that didn't detract from the experience at all, as enough hints are dropped later in the game that it shouldn't be a surprise by the time it's revealed.
The gist of the game is that you're playing as a pig, and because of that, you are very limited in what you can personally do and need to manipulate the NPCs around you in order to navigate the world. It makes for a completely different kind of gameplay experience and puzzles that are entirely unlike those you find in standard IF games. I enjoyed it immensely.
The characters were a charming mix of standard archetypes and subversions of those same archetypes (Spoiler - click to show)(the brave but dimwitted knight, the cowardly but reliable squire, the evil sorcerer, and the vain prince) and I found myself somewhat invested in their stories. (Spoiler - click to show)I especially enjoyed Tuck and Tristain's awkward friendship, as it defied both hetero and homosexual romantic cliches.
As far as difficulty, this game was on the easier side, but it wasn't so simple that it detracted from my experience personally. I think it is a good game for beginners or players who might often rely on guides and hints to finish games.
TL;DR: Wizard Sniffer is charming, engaging, funny, and doesn't require a huge time commitment. I loved it.
It's a captivating story that unfolds in a way that makes more sense as you go, leading you to understand the characters and their relationships to each other. I went into my first playthrough completely blind, so my understanding was absolutely zero when I started and the first few sections made no sense whatsoever, but this didn't at all take away from my experience. It made it more rewarding when I began putting pieces together.
The game's only weak point is that it is more of a story than a game, and interactivity mostly comes down to different choices of dialogue. I understand that this was a choice on the creator's part, and I definitely still recommend giving it a play-through, but it's best to be aware going in that you're going to get a non-traditional, non-linear story rather than an interactive adventure with puzzles.