You sometimes get the bonus, if you're lucky. Plus, you're not always going to get the item you want; I played SG maybe 3-4 times before I got the item I really wanted, and the other items were useless to me.
When I decided to try the shenanigifts it took me all my 10 tokens to get the one item I really wanted, so it depends on your luck.
If you want more than one item, rather than wanting a one specific item I'd say go for it.
If you use the power ups (2 gift, extra chance) you have a better chance of getting the item you want. IMO it's worth playing. More fun than trading anyway