I'd built the SS up to do the Mega next year as I had got an amazing deal on a new frame otherwise I would still have the Tracer. I had not ridden it at all until on one ride my riding buddy needed to borrow a bike so I lent him the Tracer and I rode the SS. I just felt more confident on it and it certainly corners better (very low BB). It does take the bigger hits better but then it should do and I think that I have been riding bigger stuff because of it. In all honesty though I reckon the Tracer could handle all of what I do it's just I'd rather be on the SS.
The Tracer does get up the hills better, is lighter and probably pedals a little better on the flat but out and out sprinting I'd say there is very little in it if anything.
My Tracer went through several guises and looking back I'd go with the following:
6 inch mode
Fox 36 with a flush fit headset to keep the BB as low as possible
Ditch the RP23 if you are a heavier rider and get a coil ASAP. Freeborn.co.uk sell CCDBs for £485
If anything happened to the SS and I could not get another I'd either go for a Tracer 2 (a few more months to wait for that) or get an Uzzi VP. The Tracer 2 looks like it will have a beefier rear end to the Tracer 1 although this does mean there should be some deals to be had on the Tracer 1 fairly soon as the shops try to shift old stock in readiness. I'd wait if it were me.
http://forums.mtbr.com/showthread.php?t=632142