Hehhehhe..!! I don't have writing skill..!! But between Nokia 2730c, 2710 Supernova and Samsung Metro S3310, I can say that Samsung Metro S3310 is the best one can get in that budget. If someone want 3G and futureproof he/she may think of looking at Nokia 2730c, But I'd say not to go for it, the 3G in 2730c is just 384kbps and no support for video calling, then what is the use of getting a 3G phone?? If someone is really looking at 3G Handset I'd suggest to up his/her budget and get a better phone.
I can mention the pros and cons of the phone I've seen:
Nokia 2730c :
1. Keypad is very hard. Fingers starts paining after entering two or three letters. Absolutely not for SMS Junkies or if someone is looking for browsing on phone.
2. Screen quality is not so good.
3. No Music keys / Volume keys on side. One have to operate manually from Music Player.
4. Loudspeaker is not placed strategically. You need to guard the speakers with your hand to get louder sound.
5. Supports photocall but the photo appears very tiny, so no one can recognize that.
6. Headphones are like the normal ones, not the headphones that generally come with phone. So using the headphone(for talking) on croud area is tough as the mic would come near to someones chest.
7. Memory Card support upto 2GB only and comes with 1GB.
Samsung Metro S3310 :
1. Screen quality is better than other two.
2. Loudspeaker is better than other two.
3. Accessing menu's are difficult than Nokia ones.
4. I found it best among other two.
5 Memory card support upto 8GB and comes with 2GB.
Nokia 7120 Supernova :
1. Keypad is good comparing to 2730c.
2. Screen size is so small.
3. Using application would be tough as of Lower RAM.
4. Loudspeaker is not so good, but Supernova comes with a dock, on placing the mobile to the dock makes the sound really good. So using the loudspeaker of public places would not make any sense.
5. Memory Card support same as 2730c.
Only Supernova comes with a data cable but doesn't make any sense as it's mere 2inch in length.
All the phones have 3.5mm audio jack(Not sure about supernova)
I found Bluetooth on Nokia better than Samsung.
Well...I must add that I've just written what my experience is. So it should be taken as comments rather than review.
As all the phones are on around same budget, taking all the pros and cons into account, I'd recommend Samsung Metro S3310.