[Seaside] Using traits in Squeak / Seaside - Advice sought

[itsme213]

I will be doing some development in Squeak 3.9 / Seaside (I have played with 
Squeak before, this time it will be RealWork). I like the idea of using 
traits, but have no actual hand-on usage experience.

Should I use traits in my work?
Know of any real deployed projects that have used traits to good effect?
Do the tools manage the cost of all the finer-grained bits, debugging, etc?
Are there any best practices I could look at?
Will using traits affect (a) possible port to VW? (b) possible use of 
Gemstone/S?

Thanks!