You are obviously right but in my case:
1) if upgrade process is not smooth (not even core's) is something to consider;
2) I did built a catalogue years ago;
3) I did hire an Agency as I stated, that PS platinum partner is an agency specialized in Prestashop
4) I purchased a theme by most popular theme developing agency I'm pretty sure you use/have used as well
Sorry but this time I have no major regrets myself 
You are obviously right but in my case:
1) if upgrade process is not smooth (not even core's) is something to consider;
2) I did built a catalogue years ago;
3) I did hire an Agency as I stated, that PS platinum partner is an agency specialized in Prestashop
4) I purchased a theme by most popular theme developing agency I'm pretty sure you use/have used as well
Sorry but this time I have no makor regrets myself
