I HAD TO setup a prestashop for one of my eCommerce projects, because my supplier was prodiving csv and other data daily and now looking forward to convert it to OpenCart as well.
What you will face with prestashop:
1- THERE IS NO COMPLETELY WORKING SOLUTION for MASS IMPORT (!)
I wrote all capitalized the above text because it's one curical function for mass import.
2- There is no completely working commercial module for mass import either. I had to buy two modules in total 100€ and had to edit the code to make them functional. Terrible customer supports, terrible language skills.
3- There is a retarded function called "building search index" which is SEMI FUNCTIONAL. I had to update my product prices on daily basis and have to rebuild search index in order to make them available to search on the site.
Guess what? There is a cron task that's supposed to handle it automatically, right?

4- NO VOUCHER, NO GIFT CODE NO THIS NO THAT. All paid modules that cost hundreds of euros.
Wait, my list is longer than this. I experience more troubles that I never had with OpenCart.
Oh my god OpenCart. I feel like kissing your ass so bad right now for being perfect and masterin ALL THE ecommerce solutions.
Any prestashop lovers welcome to brainstorm. OpenCart beats prestashop hard.