Hi Joe,
I own both the Tyros 4 and the S950 and on a daily basis am able to sit and do comparisons. There is no doubt whatsoever that the Tyros 4 is a better sounding keyboard. The T4 key bed is much better and the display much easier to deal with in various situations. On the downside I think the T4 is bulky and much larger than it needed to be.

Here is how I sum it up. If you ever owned a PSR3000 and liked it you will love the S950. If you are capable of moving a heavier keyboard with no problems you would love the T4. I am very pleased with my S950 and use it now for all my gigs. The Tyros 4 stays at home. For me, due to my recent Cervical Spin Surgery, it has become all about weight and being able to physically handle it.

Joe, I don't sing so I can't comment about the VH but most folks don't care for it and use the TC Helicon.

Joe, Feel free to email me if you have specific questions.

Deane