I have fairly extensive experience reloading for 357SIG, and I love the caliber.
You "can" resize .40 brass to work...should you? Thats all about what you feel comfortable with. I do it and I've never had a problem.
I've used a number of different bullet weights and profiles ranging from <100gr to 147gr... once again, it "can" be done without too much effort...if you're willing to take the risk.
Personally, I'd say that if you get your dies set up properly and use a 124gr bullet that has a short ogive so the case neck has something to grab onto, then you won't have any problems. If you're really worried, find a powder that takes up lots of case space and it will prevent the bullet from moving if your neck tension isn't quite up to par.
Bottom line: Do it!