Neither one is free and they are not really that similar.
Avs-Wizard is a AVS generator/duplicator. I have it and it is a good deal for the money. It has a very limited auto-submit capability but does do a good job and reducing the job of making and maintaining AVS sites. There is a review at AVSLounge that is pretty favorable.
AVSAssistant is just a preconfigured autosubmitter for AVS and it is very new. I have not really seen too much info on it and I don't believe there is even a demo.
