Pro’s and cons of even using a POS

are there any cons?
What are the pro’s?
1 location
We have owned store for 4 years now and use paper slips in triplicate for the entire time so far.

What kinds are available for a no alcohol, no inside takeout only location?

There are many options. POS Pizza is an option that I used for years. They even have a free version. Great software, user forum, support. Especially if you have never had a POS.
Revention is what we use now. Expensive. Good customer support, great especially if you will be adding more stores.
There are 3-4 other popular ones here on the forum. One of them is also inexpensive like POS pizza. It all depends on how computer savvy you are and how much you can setup yourself.
IN THIS DAY AND AGE IT IS CRAZY NOT TO HAVE A POS (unless you are laundering money, I guess, lol).
With a POS you can also get into online ordering.
For something as simple as what you have (takeout only) I would look into the free version of pospizza. You can just set it up w/ 1 computer, get a thermal receipt printer. It makes order taking so much faster, accurate, customers records, caller id, etc.

Only con is you will become dependent on it and not know what to do in the event that it goes down.

For the most part I agree with @durbancic. Today, Having a POS is a good option.

If you’re the one running the show daily and not having some manager replacing you, and if your store does not offer delivery, then you don’t necessarily need a POS even if you do over 15k/week!
I have many customers that have not invested in a POS system as they don’t think they need it.
But they are there day by day, them wives & kids!
However, where kids are taking over the family business or younger people in general start their own business, they do get involved with technology (POS, online orders, apps, etc) in order to grow their business, be competitive and potentially reach to more customers by offering more options and as a result they end up being busier in many cases but making less profit than before!
Sad but true!

Of course if you run 2 or more stores, have delivery or have a manager in place, the need for a POS System goes without saying since you’ll need something to help managing your business as much as you can.