I went with the dive rite 100' spool from scubatoys -
http://www.scubatoys.com/store/detail.asp?PRODUCT_ID=FingerSpool
I haven't gotten a chance to shoot a bag yet, so I can't report on how it works, but I have heard good things from other SB members.
Just remember to double-check that you aren't tangled in the line before you inflate and shoot the SMB. Otherwise, you might get to do a polaris instead of a safety stop!
I will be asking the DM to help me and give me some pointers on my first dives so that I can get my technique down. Supposedly, people report venting all of the air from your BC to the lift bag first is a good idea because you will remain neutral, and then you just add a bit more air from your octo/backup while you exhale in order to try and remain as neutral as possible, and let the SMB go. While it is on its way up, you can add the air back to your BC.
Good Luck and let us know how it goes!