I took the plunge a decided to switch from Tulsion to Unger resin a year ago. As a resin only purifier, I usually get through one 25Kg bag every 3 months give or take. Every Tulsion bag had varied lasting results, but I've seen a steady decline in quality and with the cost inflating so much I decided to change.
Okay Unger is not much cheaper now, but a bag is lasting on average 4 months and changing is less frequent. So it's saved me one whole 25kg bag over the year.
I have to say the resin looks and feels much better packaged to me too. But that's just my opinion.