hi shloogy!
thx for your question and the feedback. i just didn't read this. that's why I didn't answer

if you've got a question directly to me then you can post it either in the feedbackthread or in the coaching reviews. I check these threads daily, but the rest of the forum only sporadic.
basically xylere already good answers.
As I recently mentioned in coaching and video calling a reraise is almost never a very profitable situation (except we have AA or KK or are in a blindbattle situation). This is because of the gap concept - the reraiser usually needs to have a much better hand than ours in order to reraise us.
Nevertheless we can call sometimes because we've already invested money in the pot or because there is other dead money. pot odds decide wether we can still call even if we have less than 50% equity.
To make a precise decision you need to take a look at my equity chart (or any other equity comparison with possible reraising ranges)
To come to your question about AK. Where I play (NL200+) I almost never have to think about folding AK. my opponents usually reraise with a range which is loose enough to call the reraise even with a bigger stack. They reraise with JJ+ and AK (our equity is 39.8% or 42.8% when suited) or the reraise with TT+ and AQ where we have a flip. If I raise from later positions ranges of course get looser which is why I will make good profit.
But as xylere said this is very swingy. if you play dices it often happens that you get the same number 2,3 or 4 times in a row. And there the chances are 5:1. If we call a reraise we often only have 2-10% edge so something like 5:4 or 7:5 chances. This should illustrate how often we can loose there in a row. SSS is very swingy!
On thing about NL 50: ít is probably way less aggressive than higher limits. This speaks for tighter reraising ranges. The fact that much more SSSPs play there will also make the reraising ranges against SSSPs tighter: the bigstacks know our strategy/ranges very well and will therefore not reraise TT or AKo against an UTG raise from us.
Now it is your job to find out the reraising ranges of your opponents. Maybe you have to adjust my chart with another even tighter range than JJ+, AK. If you do so you will be able to find out the break even equity and with smaller remaining stacks you can still call sometimes. Give it a try!
Take a look at the advanced SSS articles: restealing, adjusting the reraising ranges and how to play against other SSSPs are really important. and btw, bss articles as well!
feel free to ask more questions, best would of course be during coaching since we can then develop a discussion with other players, too.
cu,
xarry