In the evenings, it ALWAYS drastically slows down, it can be anything between 2Mb and 60Mb, typically hovering around 10Mb and at times it is even slower than my 7.5km long backup ADSL line at ~2Mb.
Tonight I did several speed tests on Zens own tester, several on Think Broadband, several on Ookla and several on the BT Wholesale checker. Every result from Zen, TB or Ookla was less than 10Mb down. Every test from BT Wholesale checker was 50+Mb. Neither Netflix or Amazon will stream in HD but BT Wholesale checker says I am getting 50Mb+
I smell a rat! Its like BTW are rigging their speed tests to look better and mask problems.