Not sure, I think if i wasn' bothered about autograph queuing and the talks i'd do it, but it could mean getting up early.

i am considering it as i've done stewarding as almost all the cons i've attended.
upsides are usually first 2/3 rows for chats are reserved for stewards, you can sometimes choose when roughly you want to work (morn/afternoon/evening), depending on where you are placed you might get to spend some time watching the guests in action ie auto or photo room, if you are working when your auto/photo number is called you can sometimes be sent to the front (but thats only so you can go back to your duties) and sometimes there's a steward party on the last night as a form of thank you.
if i've forgotten anything im sure someone will add it.

downsides can consist of attendees blaming you and shouting at you for things that have gone wrong (if anything does but there's always something people have to complain about so tis kinda expected just smile sweetly ) possibility of missing the guest chat you wanted so much to see and im sure there might be a few other things again im sure someone will mention them.

i've lost my train of thought d'oh...

I would recommend stewarding to anyone. Yes, it can be hard work and you do get a lot of flack from the newbies complaining, but the experiences and pleasue you get from doing it is fantastic.

I personally have stewarded every event but two that I have attended since I started stewarding and not only do you get to see the hard work that goes into such events, it's also a fantastic way to meet new people.

If I was going to Fusion, you'd see me stewarding. I've already got my name down for Hyperion.