Does Big Rock Rs.99 .in domains lack any features compared to other domain providers?

Domains are just names and every domain provider charge same amount for them. It makes them costly because of all other reasons. In your case, Godaddy costed you more than bigrock's because it has great customer support and good brand image compared to the latter one. Whenever you got any problem there is always some help from the popular brands.

Apart from this the brand name also plays very important role. Most of customers, these days, prefer big brands and are willing to pay extra price for their services. This may also be the cause for higher prices in some providers and low in others.

All the providers give you your desired domains with variable prices but most opt for famous and costlier ones because there is very little possibility in closing those companies unlike new and small hosts.

There is actually time limit for each offer in every corner and business of the world. There will be slight differences in each company for each product offer at each duration to get the customer. Here, Bigrock would have got you by just Rs 99 as an initial domain registration, when you complete one year you will then have to pay around Rs 400-500 (like godaddy) and not Rs 99 at that time to continue domain renewal.

Second possibility is that Bigrock might have offered you for Rs 99 few days back and now there will be no such offer at this moment. They don't lack any features, because it is just a domain name and will be having same functionality and features irrespective of provider.