Swapped my order from 6hp to 9.9
Size wise, there is nothing in it with the length and looks like it will fit in both directions in the boot. It's a bit wider but much thicker around its middle.
Weight wise, its no longer easily carry able so trolley is definitely in order - I was going to buy one anyway for the 6 just for storage, but going for a more robust foldable unit. It's still a one person lift, but you wouldn't want it any heavier. Don't think the Mrs will be helping with then engine but if there is no other help around, I've been shown the technique to flick it up into the boot of the car.
The tiller can be folded up and down which will probably be useful. I had not realised that the forward/neutral/reverse was on on the tiller - much more friendly.
I've lost the ability to use the internal tank but had begun to think that petrol in the engine during transport was a liability. I've also lost the free bag as its not meant to fit the bigger engine. I understand that most people use old towels to protect other things when in the boot. Not sure if there is a better WAF solution?