<VV> Trying again on 134A subsitute question

[Grant Young]

Trying again. I am shopping for a large canister of 134A and notice some substitutes such as EcoFreeze that are considerably - up to 50% - less expensive. Some come with 12 LB in a 30LB canister but are $100 compared to $150 or more for 134A for the same volume. I am checking to see if anyone has any real life experience with them?
Thanks,
Grant