When responding to a post you should explain your self a little better. The OP obviously has little knowledge on the subject and your post is very vauge. Also you should know what you are talking about, the whole basis for upgrading to open source firm ware is that the original platform is linux based so yes you want a linux based routerThe GL just has linux firmware, so if you are going to upgrade to DD-WRT anyway, there is no need to pay extra for that model.
Its pretty hard to find a wrt54g version 1-4 which is what you need for dd-wrt or even better openwrt. The L is linksys way of bringing it back for people like us. IMO it is well worth it to pay a few extra buck for a brand new L rather than take your chances on ebay or go through the epic battle of getting dd-wrt on a version 5,6,7, or 8 only to find out only the micro firmware will fit.
Unless you want to spend some serious cash on a badass router like a asus the I highly suggest getting a wrt54gL.