Go for bigger one.
I don't know where you from? You can take this monitor pricing for reference.
Monitors : CRT
Brand Model Details Wh / Blk
Zebronics 15" - Ord Avail in Blk 2700
Zebronics 17" - Ord Avail in Blk 2900
Monitors :* LCD
Brand Model Details Rate
ACER 15.6" - X163 Wide 4750
ACER 17" - V173 Square 6900
ACER 18.5"* P195HQL Wide 800000 : 1 6250
ACER 19" - V193GB Square 7950
ACER 20" V203H Wide 6600
ACER 23" HD - P235H Wide + DVI 8950
LG 16"* - 1643C Wide - 30000:1 4950
LG 17" - 177WSB Wide - 5000:1 6000
LG 18.5"* - 1943SB Wide - 30000:1 6400
LG 18.5"* - 1953T Wide - 50000:1 - Dvi 6550
LG 20" - 2043T Wide - 30000:1 - DVI 6775
LG 22"* - L223T Wide - 30000:1 - DVI* 8400
Samsung 16''* 633 NW Wide - 633 NW 5500
Samsung 18.5"** 933 + 50000:1* 6850
Samsung 18.5"** 943 50000:1* , DVI 6950
Samsung 19" LD190 No Base, Photo Frame 7400
Samsung 20"* 2033 50000:1, DVI 7400
Samsung 22"* 2233SW+ 50000:1, DVI 9300
ASUS 22" Wide 8400
DELL 16" - 1609W Wide 4650
DELL 17" - 1709W Wide 5775
DELL 18.5" - 1910 IN Wide 6050
DELL 21.5" - S2209W Wide 8850
DELL 21.5" - ST2210 Wide + HDMi + Dvi 9500
DELL 23" - S2309W HDMi / Webcam / DVI 14100
DELL 24" - S2409W Wide HDMi / DVI 12900
Note: Prices(Including Tamilnadu VAT) are for chennai, It may vary from place to place.