I've been back in Austria this year for a bit and once again I made good use of my unlimited data over Drei Austria's UMTS network for 18 euros a month on prepaid. They do have an LTE radio access network these days as well but unfortunately, my prepaid subscription is limited to their UMTS network. As a consequence, I was a bit afraid that my experience would suffer due to potential congestion due to the the ever rising data traffic and investment shifting to LTE.
To my pleasant surprise quite the contrary was the case. In all places with a high signal level I tried, I could easily get sustained data rates of well over 12 MBit/s over an OpenVPN tunnel. And that was not somewhere outside big cities with few people using the network, no that was in Vienna, one of the most densely populated parts of the country.
Quite incredible for a network that offers its customers unlimited and non-throttled data for less money than most other network operators worldwide would give you a couple of hundred MB or a few GB at best. So much for the theory that unlimited data would bring a network to its knees…