Best Cena/Show match is still that Smackdown 09 match. Shame most of their PPV encounters are amongst their worst, because with the right setting and motivation they do have good chemistry.
Funk/Flair series in 89 is incredible, and when you factor in the 5 Steamboat matches on top of that Flair's year is stacked beyond belief. Both men are great showmen and performers whilst still having a workrate wrestling brain to make the theatrics and charisma part of the developing story, and both men have the subtle nuances in their craft down to a tee to really sell a feud and angle. Funk to me is the most naturally talented wrestler of all time, in terms of the ability to just know how to wrestle and act in any given setting against any given opponent and never fail to not deliver.
Wrote something about Cena's comeback a few pages back:
I am a much bigger fan of Cena than most, but I'm not about to overlook when he's at his worst, e.g the I Quit match vs Miz which was just the Cena comeback done without the savvyness it usually has.
I think a poster by the name of Walk-In summed it up best. In US wrestling you'll always get the babyface comeback which focuses on sequences of moves to even the score after enduring a gruelling workover, this is the same whether its Hogan, Cena, Austin, Rock, Lawler, Sting, Orton, Punk, Mysterio, Eddie etc. The key principle is to sell brilliantly during your workoever, to really communicate sympathy and desperation to the crowd to get them invested and to earn your comeback, to me Cena really is exceptional at this. I'm not about to say his energy burst isn't irritable given the workover which preceeds it, but to me his selling and bumping and facial expressions to sell a match during the middle sort of give him...I don't want to say 'a pass', but more along the lines of it fits the story that Cena is against the wall and needs to string a comeback together or risk losing the match, since he can't take much more punishment.
Its the same reason I adore Jerry Lawler's comeback. He'd drop the strap and have a high energy/fastly paced comeback which to some people could be poor selling, but to me the timing of the comeback as well as the brillant selling during the workover create this 'now or never' emotion in Lawler matches that pull a crowd into his comeback, and therefore I always see his comebacks as 'last chance saloon' rather than 'oh its time to get my shit in and hit my moves'. It always feels like it has a purpose, like he has to be on offence now or he risks losing the match.
Its the same with Cena and Mysterio, although Rey does it far better to me through his speed and offence not being as played out as Cena's. Still, whilst Cena's comeback can often than not be irritable and feel like no-selling, more often than not I find his superb timing essentially creates the feeling he's earned this comeback, and therefore when its timed and executed well its far better than him blowing off his opponent's offence just to hit some moves: i.e a problem I have when Kurt Angle will often 'pop up' after a big move in order to hit a move of his own, his attempts at this never feel as well timed or earnt and consequently force me to see it in a far negative light than I do when Cena has his 'fiery comeback'.