Anyone who has tried the Sonic games which came after Sonic and Knuckles (which was really just the second half to Sonic 3 but Sega devs couldn't meet deadlines) knows what disappointment is. Every Sonic game between (but not including) S/K and Sonic Mania is either slow, full of useless filler characters, stuffed with Dimps additions, 3rd rate bands trying to make it by getting Sega to put their music in the game, or all of them. Sonic Advance didn't match Game Gear games.
Sonic Mania is the only Sonic game Sega has made in a generation, since Bill Clinton was President, Marla was Donald's wife, cell phones were rare, and airbags/ABS were optional, that stands up close to the original four Genesis/Mega Drive games. Its fast, has only the useful characters, inspired bosses, and best of all, music that sounds like it belongs in a Sonic game. The levels borrowed from other games feel fresh and new, and the experience in 60 fps and 1080p is breath-taking. Christian Whitehead deserves a fat salary from Sega for reviving their company's big break.
Still tho, the amount of levels should've facilitated adding super emeralds, a la Sonic 3 & Knuckles. Having all the emeralds by Studiopolis Zone and having no more afterwards makes replay value low. Also, some levels are drawn out. Also, there could've been more original levels. There's a million hackers on Sonic Retro they could've discretely borrowed from.
Worth playing, and I look forward to the update later this year.