Linksys indeed makes the best routers in the consumer (home) segments. Cisco makes routers that are meant for the business segment. Linksys is a company aquired by Cisco. Cisco does not make Linksys routers. In fact Cisco or Linksys do not make the routers at all - the manufacturing is completely outsourced. But they have stringent quality checks.
The downside is that Linksys routers are a bit expensive and in India even more so (because of duties, taxes, dealer margins, etc.). WRT54G is about $50 in USA and around Rs. 2500/- on
eBay India.
Note that WRT54G is not an ADSL modem; but a pure router.
I have BSNL provided ADSL modem/router (UTStarcom UT-300R2U) and Linksys Wireless Router WRT54G.
The query is for ADSL modem/router.
I am pretty happy with UT-300R2U as it does the job. BSNL also provides Type IV modem/router (wireless) - Siemens SL2-141. It is priced at Rs. 1800 which I think is a pretty good deal.