When I got back into guitars I saw pics online of pedal boards with a cool looking thing with a round strobe on it, and it turned out to be the Peterson Stomp Tuner.
When I took my 2012 Gibson '61 SG Reissue back to Guitar Center to find out why it was going out of tune so often (strings were not stretched when sales guy had changed them before I picked it up) my original sales guy explained to me the strings needed to be stretched.
That is also when he told me my SG was kind of rare as it had a one piece rosewood fretboard and was made in March of this year.
That is around the same time Gibson switched over to the two piece boards from the rosewood fiasco.

Anyways, he talked me into spending around $200 on the Peterson Stomp Tuner.
It is nice, and does all of the alternate tunings (I only play in standard though) and it also has what is called Sweet Tuning which I do not exactly know if that is a tad better than standard or not.
Anyways, that is how I have tuned all of my guitars with it.

Last week when I picked up my youngest sons PRS SE Semi-Hollow, I also got the new Digitech Polytune for him.
After using it and getting use to it, I think I prefer it over the Peterson.
You can do one note at a time, and also strum all strings at once.
Both methods work great, but I actually prefer the poly one where you can strum all strings at once.

It too has settings for capo, drop tunings, and the way it displays when playing one note at a time.
I find it much easier on the eyes than that spinning strobe setup that Peterson uses.

Anyone using the Polytune one, and if so, how do you like it.
And if you have also used the Peterson one, which do you like between the two?
I may end up getting myself a Polytune and taking the Peterson off of my board.
The TC one is also a lot smaller foot print.

Peterson Stomp Classic

TC Electronics Polytune

Strum mode:

One note at a time mode: