You ask for the general consensus of auto top up: It's basically because you want to be able to win as much as possible when you have a good hand.
Ex. You don't have auto top up enabled and get dealt AA when you have 27bb. You open, get 3bet, you 4bet all-in and get called by KK, your Aces hold up and you double up. Great! Or is it?
Cause if you think about the same scenario but you had 100bb effective stacks, you probably would've gotten it all-in in that situation as well, winning a lot more because you had bigger effective stacks.
Obviously it goes both ways, since you could very well have been the other guy, who lost his 100bb with KK against AA. But the principle is this: The deeper the effective stacks are, the more skilled player will have an advantage. So the shorter the stacks get, skill plays a smaller part in your game.
Ultimately why we want to have deep stacks is because that's where the skill comes in. If we can be at a table where we are the best player, we want as deep stacks as we can get. If we aren't the best player at the table, we should avoid as much as we can to play against the better players, or just leave the table in the first place and find some softer competition. So while playing deep stacked might not be very favourable for you at a certain table, it's still important to learn how to play with deep stacks, since it pretty much gives you the strongest base, and you will actually learn to play poker "for real".
Starting out in poker by playing cash games is a great idea. When you learn deep stacked poker from cash games, it's easy to make the transition to tournaments, since playing with shorter stacks is easier. But to go from long time tournament grinder to cash games can be a lot tougher.
If you want to keep track of your winnings and losses in a session you can get something like Holdem Manager or PokerTracker. I don't like looking how much I'm up or down mid session though. If I see I'm up a lot it makes me play more passively to try and protect my winnings, which isn't optimal.
So I would say use auto top up if you are looking to improve your game. It's going to be way better for you long term.