5.Nxf7 has been pretty much solved by this group. It is equal.
5.Bxf7+ has been partially analysed on this group. A few thoughts:
The old main line of 6.Bb3 (or 6.Bd5) 6...Rf8 has three problem lines in which I can confidently say that black is refuted. So this leads to our current way of playing.
5.Bxf7+ Ke7 and now the two main lines:
6.Bb3, the modern plan of 6...Qe8 seems to be best. Black needs to be as fast as possible to stay in the game. The idea here is to go d6->Bg4->Qh5->Raf8 to put the kingside under massive pressure. 6...d6 would be ideal, but there is a problem line with 7.Nf7 where black is at a disadvantage without any play.
6.Bd5, the plan of 6...d6 works here as white is blocking d5 with his bishop. The speed here helps black greatly. The plan here is the same as with 6.Bb3 with the Kingside pressure and development. 6...Qe8 probably works as well, but if you have the option of d6, you usually want to play that as soon as possible. There should be more testing though.
So, if you are going to post games, the current main lines should be looked at:
5.Bxf7+ Ke7 6.Bb3 Qe8
5.Bxf7+ Ke7 6.Bd5 d6 (or 6...Qe8)
I would also like to point out that 5.d4 is showing to be a possible problem line according to pfren, but white seems to rarely enter the line. It would be good to take a look at this.
Please post in game editor with analysis. Do you think that after 5 Bxf7+ white has an advantage? 5Nxf7+ is bad for white. Right?
Please post your games when you played white or black. Thanks a lot.