Tempo T815 Unlock Now $2- $4?

Hmm I noticed on ebay there a number of sellers that unlock this phone for the $2-4 mark

interestingly one Australian seller has it $3 for a general zteunlock and $4 unlock for the specific model zt815 with IMEI starting 8654460 (Telstra)

There is also a UK seller selling for $3 with 65K feedback at 99.9% positive.

Its a lot cheaper than the $10 people was forking out several month ago.. anyone have success with these cheaper unlocks?