When I get up to speed via the motor I can turn off and not have too much trouble but I wouldn't want to lose power while I'm out on a commute with the 500 watt + Stealth.I ordered the 250w stealth with LCD. (Lower power for work lol)
I do have a 1000w ebike which is too heavy.
My Trek 7.5FX was taken in yesterday for a conversion with a 250 watt and that will be fine pedaling with the extra weight without power if ever it happens.
I'd actually tried a Trek 7.3FX with conversion and took it for a test ride without the power on and it was OK.