Which laptop to buy for home office, 4 choices from Lenovo/Dell/Asus

[hemang]

I am looking to replace my Dell 1555 which is almost 5 years old. I need a laptop for my office and personal use. I administer 4-5 computers on my small office network so I would prefer Win7Pro which I am currently using also. Not sure if Win8 is suitable in a mixed environment of XP and Win7 computers. I also use some old computers so need XP mode.
I also use EssentialPIM, KeePass and TrueCrypt containers so I need these to function. I think TrueCrypt has a problem in Win8.
I use the laptop at home also in humid and hot conditions, not under air con. So would prefer one which does not heat up too much and also with more battery backup.
I also use CAD and other apps so have preferred a laptop with dedicated card.
I have checked these few laptops available online in India, can anyone suggest the better one :

Lenovo Z510/59-398016
Processor Core i7 (4th Gen)
Variant 4702MQ
Chipset HM87
Brand Intel
Clock Speed 2.2 GHz with Turbo Boost Upto 3.2 GHz
System Memory 8 GB DDR3
HDD Capacity 1 TB
SSD Capacity Yes, 8 GB
Operating System Windows 8.1
System Architecture 64 bit
Screen Size 15.6 inch
Screen Type HD Anti-glare Display with LED Backlit
Dedicated Graphics Memory Capacity 2 GB
Graphic Processor NVIDIA N14P-GV2
Power Supply 48 W AC Adapter
Battery Cell 4 cell

Brand Dell
Model Name Inspiron 3537/3537781TB2B
Processor Core i7 (4th Gen)
Variant 4500U
Chipset Mobile HM76 Express
Brand Intel
Clock Speed 1.8 GHz with Turbo Boost Technology Upto 3 GHz
Cache 4 MB
System Memory 8 GB DDR3
HDD Capacity 1 TB
Operating System Windows 8
System Architecture 64 bit
Screen Size 15.6 inch
Resolution 1366 x 768 Pixel
Screen Type HD LED Display with True Life
Dedicated Graphics Memory Capacity 2 GB
Graphic Processor AMD Radeon HD 8850M
Battery Backup Upto 3 hours
Power Supply 65 W AC Adapter
Battery Cell 6 cell

Brand Asus
Model Name X550LC-XX160D
Processor Core i7 (4th Generation)
Variant 4500U
Brand Intel
Clock Speed 3.0 Ghz
System Memory 8 GB DDR3
HDD Capacity 1 TB
Screen Size 15.6 inch
Resolution 1366 x 768 pixel
Screen Type TFT Colour Display
Dedicated Graphics Memory Capacity 2 GB
Graphic Processor NVIDIA GeForce GT 720M
Battery Backup Up to 3 hours
Power Supply 65 W AC Adapter

Brand Asus
Part Number X550LD-XX082D
Processor Core i7 (4th Gen)
Variant 4500U
Brand Intel
Clock Speed 1.8 GHz with Turbo Boost Upto 3.0 GHz
Cache 4 MB
System Memory 8 GB DDR3
HDD Capacity 1 TB
Operating System Free DOS
System Architecture 64 bit
Screen Size 15.6 inch
Resolution 1366 x 768 Pixel
Screen Type HD Glare Display
Dedicated Graphics Memory Capacity 2 GB
Graphic Processor NVIDIA GT 820M
Power Supply 65 W AC Adapter
Battery Cell 4 cell
USB Port 1 x USB 3.0 (If this is really the case, it is useless)

 

[i7Baby]

Brand wise - Asus then Lenovo then Dell. In fact - don't get Dell at all.

The Lenovo has a weak graphics card but good cpu. The last Asus has a weaker cpu but better graphics card

If you want a lot of codgitating done, get the Lenovo. If watching movies and playing games etc is more important, get the last Asus

If they are all the same price,

 

[hemang]

Brand wise - Asus then Lenovo then Dell. In fact - don't get Dell at all.

The Lenovo has a weak graphics card but good cpu. The last Asus has a weaker cpu but better graphics card

If you want a lot of codgitating done, get the Lenovo. If watching movies and playing games etc is more important, get the last Asus

If they are all the same price,

Thanks for the quick reply. Between the 2 Asus models, which is better?
What is codgitating?
Approx prices in US$ are :
Lenovo Z510/59-398016 : US$ 980
Dell Inspiron 3537/3537781TB2B : US$ 1030
Asus X550LC-XX160D : US$ 870
Asus X550LD-XX082D : US$ 920

Awaiting some more opinions based on my use. Can I put Win7 Pro in the Asus, drivers would be available?

 

[alicepattinson]

I would prefer Dell/HP

 

[i7Baby]

I'd go for the last one : X550LD-XX082D

 

[i7Baby]

I would prefer Dell/HP

We get many more problems reported with especially Dell and then HP here

 

[Noaman Khalil]

go with the i7 asus (X550LD-XX082D) my friend it is a trustworthy brand and will be worth your wild for every rupee you spend I know because I have used all the brands and I think asus is the best among them btw I also picked this because it has the 820m graphics which are new and power efficient and powerfull!