I have made some calculations here , if Im wrong please someone help me but:
If you upgrade on a year bases to premium account this is what you get:
for 99 per year you have:
L$300 weekly x 52 weeks = L$15.600 (which is about $62)
so if you just subtract 99(annual)-62(weekly rent), that means a year on SL is just $37, which is really a bargain, and in addition you have a one time L$1000
so for me thats the way to go
Linden Dollar Rewards
As a Premium member, you get a one-time 1,000 Linden Dollar sign-up bonus and a 300 Linden Dollar weekly stipend to spend on goods and services like avatar fashion, nightclubs and games.