We started with Spelling Workout for 1st grade last year and didn't like it. This year (2nd) I bought Natural Speller and we are just working our way through the 1st/2nd grade list, nothing fancy. I think my daughter is a natural speller so probably anything would work for her.
I'm not sure if we will stick with Natural Speller for next year. I really think I want something that is more prepared. I'm looking forward to hearing what everyone else is using.