I lived there for a number of years.
First moved there when I went to the Poly (befiore it got delusions) and left eventually after I got married and we decided that Edinburgh would be a better place to raise any kids.
I lived in a little road called Ash Drive at the southern end of the town just down the hill from the aforementioned scenes from the Police, Camera, Action sets. The Hilltop was not an area you went unwary. I could recount many tales I witnessed and heard of, none pleasent.
The town centre, like all town centres became a concrete pit, the only highlight being the weekly market even if all that was to offer was the usual cheap tat and old cabbages.
The Galleria was the biggest mistake ever. It was initially set up to be a high end market that would not compete with the place in WGC, but they were forced due to non rental of units to lower thier standards. After TK Max set up shop, they were sued by the WGC place, as apparently deals had been done, and us rate payers were left with the tab while those responsible kept thier commissions and walked away.
On the positive side, the old town was lovely, although we were once thrown out of the 7 (or 8?) Bells once because one of us sat on a chair that was just for decoration if you would believe. This pub claims to be the inspiration for the inn that Bill Sykes stayed at when he fled London in Olliver Twist.
The best parts though are the rail link into London and up the east coast and the road links around. While living there I worked in Potters Bar, Enfield, London, Andover, Harlow and Leamington Spa for a number of employers and customers.
ETA
As for the price difference between Hatfield & Potters Bar ... Brookmans Park used to be the ultra posh bit. and Potters Bar seemed to think it was connected somehow.