Last night was first real workout - Sleeping Beauty:
Unlocked and mounted the bike as if I were outside. Absolutely no issues with falling over, its like riding a bike 
At first I fought a little with handlebars, it feels a little odd but 30 minutes later it wasnāt an issue. The ālearning curveā is pretty short, its kinda like riding a bike but kinda not. But better than fixed position.
Hit the first intervals and immediately noticed my pedal stroke was sloppy and wasting energy - a lot of rocking forwards and backwards. Put some attention into pedal stroke and that made it better. Didnāt ride long enough to test ācomfortā but am very happy buying E-Flex for nothing more than the awareness of pedaling economy. Iāve never ridden rollers but this seems to be the happy medium between fixed trainers and rollers. 