If you want to look into free offerings there is Vixen 3 (that should be ready for release this year, still in beta) and HLS.
HLS has just been out for a year but is a very capable sequencer already, and Joe Hinkle who is responsible for it listens to his users and is very quick to implement new ideas. I used HLS this year for a small non audio display since I had som issues with LSP. And I was very pleased with how it worked.
After my show finished this year I did download HLS and play around with it. I was really impressed with it. Like slite said Joe Hinkle has done an amazing job and created a very robust sequencer for it to be free.
For 48 channels then LSP may not be the best choice, LSP really shines with larger pixel based sequences, if a large pixel based diplay is what you want in the future then it may be worth going straight with LSP to save any heart ache in changing software later down the track, otherwise with 48 channels Vixen is more than capable and is free, LOR is easy to use but to run DMX you will have to buy the top priced version. HLS may be another good free option as well, but i havent really used it so I cant really speak for it. The best way is to download them all and have a play with them as they are either free or have free demos.