I got my captivate from a TE member here. The member was in Kolkata and shipped it to Bangalore. So it was in excellent condition and it was not a group order. I had to order a captivate, since my original one was stolen.
Importing is not a hassle but involves lot of steps and also requires you to have to be patient. I usually never import myself since I live between Denver and Bangalore.
My pick is captivate because of design only. The vibrant looks like an iphone but captivate looks a whole lot different. Also it has metal battery door. So it is of personal preference only. Vibrant and Captivate has same hardware and software.
That is the problem. See, I keep captivate and other phones because I have to travel to Denver as I am here in India on visa basis. So worst case something happens to it, I can get it repaired for free if within the one year. But in your case, which I do not know, it might be difficult if you do not travel there. So using a phone without warranty is risky no matter how much money you spend. It is all about taking risk. So being careful would be logical.
You can buy a Galaxy S for 20k from online with 1 year warranty and peace of mind. After all it is same as other models. The international galaxy S is the father of all Galaxy S models IMO

You still get the Super Amoled and 4 inch screen, which is super sweet as you said
Else, my other advice for you is to go with Nexus S. It is cheaper and is available for 18.9k with 1 year warranty. It is an google phone with 4 inch super lcd screen. Super lcd screen is also good, only difference is super amoled has accurate dark colors while super lcd has accurate light colors. It is an developer phone with excellent design and gets updates directly from google so you are taken care of. While we have to mod galaxy s, nexus s will be the first model to get the next Ice cream sandwich update.
Nexus S Specs -http://www.gsmarena.com/samsung_google_nexus_s_i9023-3910.php
Nexus S deal at ebay -
NEW SAMSUNG GOOGLE NEXUS S i9023 16GB ANDROID2.3 Mobile | eBay
I can definitely help you get one, if you are interested in captivate or vibrant. Please PM me and we can discuss. Also be sure to check TE member's market as there are phones like this always on sale.