I really like it.
The games are nice and especially the shop is special; has a lot of unique items such as picture books of a lot of classical tamagotchis, cellphones that allow you to call a few of them, and a lot of different, exclusive stuff, making the blue home deka something of a tamagotchi artifact collector.
It can send money and items to the ketai and aka ketai (though I've heard the items might look different on the aka ketai).
It can also send money to entama and uratama.
You save money for upgrading your house and buying pets. You can go to school and speak to other tamagotchi students (in japanese, but still...)
I've had heaps of help from this guide: ... Nevermind, the page (tamasquare hosted by peppersoup.net) seems to have timed out. Such a pity, it was an excellent page with complete info on a few rarer tamagotchi versions...
Anyway, I'd definatly recommend the home deka, you can always ask here if you need help with anything. I've seen quite a few being sold cheaply on ebay lately, so keep an eye open and you might have luck!