Here in the US, most of our fried potato strips are from a few large scale potato farmers, are processed in a central location, flash fried and then chilled, bagged, and shipped to the fast food restaurant of your choice.
In-and-Out Burger cuts their own potatoes fresh and fries them up on demand in their various locations. You can definately taste the difference.
Nutritionally, fried potato strips are a poor choice. High in calories & fat, low in other nutrients. As a comparison, the potato itself (before cut & deep fat fried) is a powerhouse of complex carbohydrate, vitamin C, and fiber.
As for preference in flavor (a combination of the taste of salt, sweet, sour & bitter - cause you can't taste the fat) and the aroma (fat carries all the smells - remember way back when McD's cooked in beef tallow???? you could smell those fries a mile away); I like the steak fries (thicker cut) and used to enjoy Fatburger's version (before I made a valient attempt to give up fries completely this year).
So, how has my attempt to give up this non-nutrative food gone this year? Not too bad. I think in the past 9 months I have had an order of fries 4 times (I had a really bad week at work and fell into some old habits in the Wendy's drive-thru).