From Canon's website:
G90
http://cweb.canon.jp/wordtank/g90/index.html- Features: Touch-panel kanji recognition and search - also sound function available
Dictionaries:
- Chinese - Japanese/Japanese - Chinese dictionaries: 6 different ones
- Chinese conversation dictionary
- Oxford English - Chinese dictionary
- Oxford English - English
- Oxford Thesaurus
- Genius English - Japanese
- Genius Japanese - English
- Katakana words dictionary
- Kanji
- Japanese thesaurus
- Japanese proverbs
- PC vocabulary
- Modern Chinese new words dictionary
V80
http://cweb.canon.jp/wordtank/v80/index.html- Features: Sounds available, also touch-panel search
Dictionaries:
- Chinese - Japanese/Japanese - Chinese dictionaries: 2
- Chinese conversation dictionary
- Oxford English - Chinese dictionary
- Oxford English - English
- Genius English - Japanese
- Genius Japanese - English
- Japanese - Japanese dictionary
- Kanji
- Kanji proverbs
- Japanese proverbs
- Guide to pronouncing people's names
Both have sound function, though.
From Canon's description, V80 is a bit simpler in its contents and more geared towards convenience for travelers (as well as learners), and G90 is more for advanced learners (more extensive range of dictionaries), also comes with extensive Japanese dictionaries.
As I'm not a learner of the Chinese language, I am not familiar with the different types of dictionary contents for the language.
You might want to check with the manufacturer/shop again if they have the manual for G90 - because that one has more English functions, they SHOULD have the manual in English as well somewhere :)
If you are sure you want to exchange it, if you have the receipt from the shop, as well as all packaging (box and everything) from the product, they SHOULD give you an exchange.
