After Persona 3 Portable and Persona 4 Golden, I wanted to try out the parent game series, Shin Megami Tensei - and apparently SMT4 is a pretty good starting point. I even bought my n3DSxl for this game, more or less.
Take away the Japanese schoolkid socialising/drama aspect of Persona, add a more gritty, apocalyptic tone, and the ability to talk to demons, and that's more or less SMT. The bulk of gameplay involves turn-based battles against enemies (generally demons), where you have several combat options to attack the opponent's weaknesses. The press-turn system lets you get extra turns if you successfully hit a weakness, or score a critical attack. Often critical attacks will also cause your characters to 'smirk', which in particular makes them incredibly difficult (impossible?) to hit. This is particularly aggravating when the opponents smirk.
The other combat ability, mentioned briefly before, is the ability to talk to demons. In persona, you more or less randomly gain personas via card mini-games after battles. SMT instead uses a system I much prefer - during battle you can talk to the opponents and convince them (either by words alone, or gifts) to join your party. Some of the dialogue with the demons is surprisingly amusing or interesting.
Overall, I much prefer the combat in SMT to Persona, even though they are very similar.
SMT4's story is fine, though nothing particularly amazing. You are given opportunities throughout the game to respond to questions in manners which will affect your alignment, which is used to determine which ending path you take. To me, the endings themselves strongly suggest that the Neutral path is the most worthwhile, both from gameplay and story perspectives. It's also the trickiest to get.
There are negative aspects to the game - in particular, navigating the map of Tokyo once you get there is quite a pain, it's hard not to suggest finding a labelled map online so you know where all the locations are. Sometimes quests don't even take note of the location you are expected to go, and you need to remember, which can be difficult when you put the game down for a couple of days.
The SMT series' difficulty is also notorious - in this case, one early boss is quite punishing, and you may need to back off for a bit. Not to grind, mind you, but to get the right demons in your party to not be obliterated by the boss' attacks. In general this is the case with battles - getting demons in your party with the right resistances/counters is crucial. Outright level grinding isn't really very important. In fact, even as a high level character, when you go back to early locations in the game, it's still entirely possible to get wrecked by pathetic opponents who happen to hit your weaknesses.
That being said, some boss battles do feel like randomisation affects the outcome - you can try multiple times and NEARLY finish them off, only to be hit by exactly the wrong attack for that moment, resulting in a party wipe. Perhaps this is 'good' tactical AI by the opponent, but it can get frustrating.
On the other side of the coin, by mid-game your character and party are likely to be extremely strong and encounter very little trouble whatsoever other than the odd boss character you haven't been prepared for. The final boss(es) are beatable to the point where I was expecting another ultimate boss to show up, only for the end cinematic to begin. In that way, the endings are a bit of a let-down.
During most of the game, you have an AI ally in your party - unfortunately, depending on their abilities, they can actually harm you more than help. Having them hit the opponent boss's strength, causing them to smirk, is quite aggravating, but there's really not much you can do about it.
Other than those quibbles, SMT4 is certainly enjoyable, the graphics and music are good-to-great, 3d is actually utilised quite well (I'd never have thought I would ever turn the 3d effect on, but generally had it on for this game), and the gameplay is fun. Persona's dungeons always annoyed me, and I kind of wish I didn't have to play that part of the game, but the equivalent in SMT4 gave me no issues at all, combat was never as much of a chore. It might not have schoolgirls, but definitely worth a go.