I can't say that I have an experience based recommendation for you on that subject. But what I can say is that I am replacing all 6 of my rubber AV mounts with new OEM parts for my 288 I'm building and will be running the front AV spring. XP_Slinger's 288 is set up this way and I do like the way it handles. That said, I've never disliked the my 3-series saws for their spring mount system either. I'd be curious to run a 288 set up with all springs to see what it's like after getting accustomed to a rubber mounted one...
Hmm... maybe since XP_Slinger has his 288 done up with all rubber, I should experiment and get all springs so we can compare????