I don't have a scrapper 6, but personally, for a knife that size, I'd rather have SR-101 or INFI. SR77 is great on a chopper, but on a bit shorter blade like the S6, I value edge retention more than overt toughness.
If you can snag a good price on an S6 on the second-hand market, by all means go for it, as SR77 is still a great steel, but if I had to choose one six inch knife, the S6 wouldn't be the one.
Personally, for me, a six inch knife is in a sort of limbo area - a little bit too big for fine tasks, and a little bit too small for chopping. I'd rather step up to a SOD-sized blade, or down to something like the scrapper 5. Just my preference, your mileage my vary.