I like how SupahCow said it, but I'm guessing you want more opinions.
Well, I was in your position about a month ago. Here are the topics I made:
https://www.tamatalk.com/IB/topic/192912-plus-color-of-4u/?view=findpost&p=3329728
https://www.tamatalk.com/IB/topic/192931-tamagotchi-ps-help/?view=findpost&p=3329897
https://www.tamatalk.com/IB/topic/193133-which-new-colour-tama-gahh-opinions-please/?view=findpost&p=3331233
Yikes...
Anyways, I ended up with a P's and an iD.
So let's start with a list:
TMGC+C: The simplicity gives off a nice vibe and it has more original characters, although, looking back at what you said, you may get bored of this one... and it's hard to find a good price...
iD: These ones can get a bit expensive. They're probably my favorite because of the super original, recognizable characters.
Some people find them simple and boring, but there is a
lot of downloadable content for it.
iD L: Now these are a lot of fun. Tons of things to do. However, the characters give off a more alien vibe, rather than the usual cuddly vibe. I find the characters a bit humanized but I like the majority of them.
P's: This one is like the iD L, except it replaces some things. It has only 5 tamapets (iD L has 10) and you can't garden, instead you go to work. This one really is like the V4/.5
4U: I don't know much about this one... If you don't have a Samsung S5 or Nexus 7 (2nd gen.) then it really isn't all that fun.
4U+: Same thing except the + is definitely more expensive.
I'd start by looking up the versions you're most interested in at
https://tamagotchi.wikia.com/wiki/Main_Page
Obviously, it's smart to do some research and watch a couple videos on each version.
Seeing as language isn't a barrier, all you have to do is ask yourself a couple questions:
Do I have an infrared or NFC device? If not, go with one of the devices with infrared, since it's cheaper to buy a irda usb or a cheap palm treo.
Am I willing to pay a ton of money? Reading your first post, it looks like the answer is no, since you're getting one to improve your Japanese. So you can cross out TMGC+C and 4U+ (unless you find a good deal
).
Do I like the more original characters or the newer ones?
Do I like the thought of downloading more content to sort of customize it or having it built-in?
Here are some links to the cheapest ones on amazon (there are AMAZING deals on ebay too, for example I got my iD for 19 + 7 shipping USD):
TMGC+C: https://www.amazon.com/Tamagocchi-Plus-Color-Screen-Japan/dp/B001QTLT04/ref=sr_1_18?ie=UTF8&qid=1456882478&sr=8-18&keywords=tamagotchi+plus+color
iD: https://www.amazon.com/Bandai-Tamagotchi-iD-purple/dp/B002QUYQ0M/ref=sr_1_1?ie=UTF8&qid=1456882587&sr=8-1&keywords=tamagotchi+id
iD L: https://www.amazon.com/Bandai-Tamagotchi-iD-L-PURPLE/dp/B004LLI3FI/ref=sr_1_8?ie=UTF8&qid=1456882627&sr=8-8&keywords=tamagotchi+id+l
P's: https://www.amazon.com/Bandai-Tamagotchi-Ps-Blue/dp/B009IE112A/ref=sr_1_1?ie=UTF8&qid=1456882736&sr=8-1&keywords=tamagotchi+p%27s
4U: https://www.amazon.com/TAMAGOTCHI-4U-WHITE-Tamagotchi-White/dp/B00LGBMSMK/ref=sr_1_6?ie=UTF8&qid=1456882627&sr=8-6&keywords=tamagotchi+id+l
4U: https://www.amazon.com/TAMAGOTCHI-4U-Bandai-Sky-Blue/dp/B00ZHJGYXG/ref=sr_1_54?ie=UTF8&qid=1456882802&sr=8-54&keywords=tamagotchi+4u+%2B
I hope I didn't overload you with links,
Now the links from amazon were the cheapest ones on
amazon, but there are always other websites
Unfortunately, as I was copying and pasting the links, I noticed the P's and iD L have gone up $10 in price.
Weirdly, the TMGC+C has gone down $20-30 in price!
Hope I helped! (please check with your eye doctor after reading all this
)