DIrect comparison:
Before I got seriously ill about 18 months ago, my best time for cycling to work on a 10kg road bike was 47 mins (12.5 miles). I could sustain 20mph on the flat. After being ill, I had to get a pedelec (or stop cycling, but that wasn't an option) - my best time on that so far is 52 mins. It really dosen't like going over 18mph; it's a Salisbury LPX and just dosen't have the gears. Well, it didn't, I've just bought a 53 tooth chainring to replace the 38 tooth one that comes as standard, this may make a difference.