Excellent

It is a good phone, easy to use, better than blackberry i used before. We can use 2 sim cards.
•Dual-SIM (dual stand-by)
•Quad-Band GSM and dual-band 3G support
•7.2 Mbps HSDPA
•SIM switch in notification area
•3.14" 256K-color QVGA TFT touchscreen
•832MHz ARMv6 processor, 290MB of RAM
•Android OS v2.3.5 (Gingerbread) with TouchWiz UI
•160MB of internal storage, hot-swappable MicroSD slot, 2GB card included
•3.15 MP fixed-focus camera with geotagging
•GPS receiver with A-GPS
•Wi-Fi 802.11 b/g/n, Hotspot functionality
•Stereo FM radio with RDS
•3.5mm audio jack
•Document viewer
•Accelerometer and proximity sensor
•Swype text input
•MicroUSB port (charging) and stereo Bluetooth 3.0
•Social network integration

If you think, first business then pleasure, this model is built for you

This is only one advantage, DOUS (dual SIM). The rest is average.
The size is fear, the screen size could be bigger, instead of the 2 buttons "Menu" & "Back" whitch also don't glow or lighting in dark. The screen must be improved.
The camera is very average and even poor, no flash! Macro for tesxt impossible or close objects, good for indoors, lighted areas, nice function for simile capture.
The big issue - dual sim working excellent, easy to change between sims, I've test it with several Cellular providers GSM, HSPDA, and all was working great!
The music sound is average up to good.

If you travel a lot or have two cellphones that's the model for you, only business and small games or music moments.

The first really usable dual SIM entry level smartphone

This is the first usable dual sim phone from reputable manufacturer that supports 2G and 3G networks. I had to carry two phones which I found to be extremely inconvenient, and Y duos finally is a solution.
Y duos (just like Samsung Galaxy Y it is based on) is an entry level phone, which shows across the board in its features. It has low-res screen, very few sensors and very primitive camera. There are a few improvements in Y duos compared to Y, but those are minor.

Having said that, the phone is surprisingly usable. Battery life is ~2 days in real usage, call quality is good (no dropped calls whatsoever), sound quality is decent. Dual SIM integration into menus and phone functionality is good and intuitive. 3G works great. The range of Wifi is not great but it is very stable.

If you are looking for a relatively cheap entry level smartphone with dual sim functionality – look no further. If you want more features, you might want to take a look at just announced Galaxy ACE duos (GSM edition).

Dual SIM limitations in Galaxy Y Duos:

- Y Duos implements “Dual SIM standby” mode. It means that if one line is in use, a call on the other line will get “busy” or “not available” response.

- Only one SIM can be in 3G mode, the other one is forced into 2G. If both SIMs you want to use are from 3G only networks, Y duos is not going to be useful for you.

- You cannot use 3G data connection and talk on the 3G only SIM at the same time.

i prefer have two phones

is very slow, they have to do better phones with dual chip, the screen resolution is very poor and the memory and processor are to down

good valur for money

it is very good ,very good battery back up .only thing screen is little small campare to size of mobile if you compare with other mobile