Hi Ed & Simon - here’s my review for our Mark 2 450 & 520 e-bikes It has been a while since we received our 2 Mark2 E-Bikes and I have held off submitting a review until we both had time to ride them well and get use to them. That said I have now completed over 100 miles (including a week commute to work - 50 miles!) They are both well put together machines - from the frame finish; sturdy and very tidy joint welding to the elegant powdered black and white coating finish and detailing in yellow stands out well. Components are of a high standard and specification that will withstand many miles of use. The Shimano Tiara 10 cassette 12 - 28 provides as good range of gears to use across any terrain - with or without power assist selected. Similarly the Shimano disc brakes as smooth and very efficient in stopping a heavy bike. The inclusion of suspension forks adds to providing a more comfortable ride over rougher terrain - or poorly repaired roads… Saddles on both bikes are comfortable and remain so on longer rides - although we are using cycling shorts too! The power assist element works efficiently and effectively across the range of power settings and allows for a flexible riding attitude. Being able to adapt the setting for upcoming changes in terrain is easily selected via the simple push button selector and kicks in with ease. Charged battery life lasts well - I completed a full week commute on one charge - recognising that whilst my route undulates and much of my speed has been above 15.5 MPH where power assist cuts out. Additionally I have not been using a high power assist level is whilst on the flat which has obviously allowed for a high mileage between charges. A few minor things that don’t quite meet the mark. The 450 does not have any bottle cage studs on the down tube whilst the 520 does - so unable to mount a bottle and pump holder. The kick stand springs are not quite strong enough to stop them from bouncing when on rough terrain… the back stays on the frame has recessed holes fro a frame mounted stand why was this not used? Lastly these e-bikes whilst heavier that a standard bicycle have been a game changer from my wife’s perspective. She is a hesitant and unconfident cyclist and has now completely changed her attitude towards cycling. With the power assist kicking in as soon as you turn the pedals has meant that she has found a level of stability on setting off that she has not been able to again in the past. THe ability to maintain a speed heading up hill without to much physical effort with the correct level of power assist selected is in her words is bring a joy to cycling she has never had. I have a couple of minor niggles that I will contact you directly about to resolve. Overall very pleased with these e-bikes and will be riding them for may years to come.