I've actually had good call centre experiences with them, dealing with the Mumbai operation and the Dubai one. When I call in from my registered number (I'm EK Silver) They greet by name (even in the local call centre) and recently after pricing a date change and giving them all my credit card info the call dropped and they called me back within 10 seconds to complete the change.

Just once had some confusion about possibility of creating a mixed fare ticket, when I was trying to get a Flex/Flex Plus combination in Y as I was would've been 300 miles short of Gold otherwise. Worked it out in the end and was able to successfully book a 6-leg open-jaw multi-city JNB - DUB - HYD - CPT via the call centre on specific requested flights and fares without much hassle incl. a 72hr fare hold.

EDIT: To be fair, they stuffed up the above itinerary a tiny bit, by booking JNB - DUB - CPT with a nested DXB - HYD return in it (i.e. a 90-day stopover on the first inbound sector in DXB which connects on to HYD), which means now, where I've completed up to HYD I've not earned miles for DUB-DXB yet as I'll get those only when I complete the sector, i.e. DXB - CPT. This came to light when I enquired about upgrade cost DUB - DXB and was informed I'd have to upgrade DUB - CPT, even though the connecting flight to CPT is in January (and DUB-DXB was two weeks ago)...not a major issue though, going to lose 50 miles because of it (as opposed to DUB - HYD + HYD - CPT, as I am getting DUB - CPT + DXB - HYD RT)

EDIT 2: If anyone cares, flying Y Flex, DUB - CPT upgrade to J cost was around $800 one-way