It all depends on how you ride the Vado SL, assist levels, your own weight and fitness, wind conditions, road condition (good tarmac or slow draggy tarmac that the UK is full of, or cycle paths & gravel roads etc) and hills - how long how steep? For example I did 42 miles the other day with 25% of battery left after 3585ft of climbing. I might have used less, but with the weather being so rubbish last few months, I'm not that fit and so even though the day was gorgeous I was tired heading for home and used more assist in the last 10 miles.
But those figures are also misleading because I tend to ride as much as possible without any assist. Around 50% of that ride was without assist, 35% in eco and 15% in sport & turbo. I use the motor for hills, headwinds and to get me home when tired. After 3 years of playing around with assist levels etc and using it like this, I now know 30 miles is fine on the battery alone, and bear in mind its very hilly around here, up to 45 miles I need to be careful with route planning and assist usage and beyond that - when I'm fit enough - I use the range extender. Of course when I get fit enough to do 50 miles plus I'm also fitter and so use less assist so that helps as well.
Last summer while at my brother in law's house near Reading, I did a 30 mile spin on my ordinary road bike (non electric) it's flat as a pancake around there and it was so easy without hills! Didn't need a motor at all.
Of course if you bought the Vado SL for speed not so much to hep with fitness or range then that's not what I'm interested in. I like going fast but didn't buy the bike to go faster then my other non electric bikes by leaving it in turbo full time. Plus the 15.5mph cut off not going to help much there.
