Usually, people are very price conscious early on and are not very willing to spend $200+ on their first set of real headphones. So they purchase the SR-60/SR-80/MS-1. After a few minutes of listening to them, they are amazed/blown away and are already planning their next purchase. If you're willing to spend a decent amount of money upfront, then go for the 325is. At home, I switch back and forth between these and my RS-1s. IMO, they are on the same level...they just have a different signature. The 325is are considered one of the most detailed cans on the market and have a bit more detail than the RS-1s. Now, if you're looking for better bass extension, then perhaps you can take a look at the RS-2. Or, if you're unwilling to spend that much money, the SR-80s or 225s are a good bet. If you decide you don't like them, you can resell them for 80-90% of their value here. But, if you go straight for the 325is, then you can skip that first step altogether.
The absolute best advice, obviously, is to find a shop around you that will let you demo these cans or go to a head-fi meet. Then you can make an informed decision and decide for yourself where your money is best spent.