Green Man Gaming offers preorders of downloads of Sonic and All-Stars Racing Transformed for Windows
for $26.99. Coupon code "GMG20-PJFEW-Y16HK" makes it $21.60
. That's the lowest price we could find by $5, outside of the price below. It's set to be released on or around January 31.
Of note, Amazon has it bundled with a $5 video game credit for $26.99.