We've had the 1.5 Sport for a while now and it is very good overall, performance compared to our old 1.4 Mk1 Sport is noticeably better. It's no hot hatch but there is certainly enough power and torque is decent enough for a Jazz, definitely better than all the other Jazz's I've driven so far.
Fuel consumption is on par with our old 1.4 MK1, not noticeably more thirsty though I'm sure if I worked it out properly it might be slightly worse but given the better performance and driveability its definitely not an issue for us.
Insurance, we're on a multicar deal paying around £400/yr.
There are a few things to be aware of that are small annoyances for us...
1. Squeaky clutch pedal - We had this problem for a little while but then after spraying some lubricant on it it seems to have gone away.
2. Engine hesitancy at just below 2k rpm - Sometimes at a certain rpm below 2k, there seems to be a sudden dip in power which is a little annoying but not a "problem" as such.
3. Rear head room - As the interior trim on the roof curves in, some people will find it touches their head when sitting up straight. I think the car is not as tall as the MK1 so there is definitely less head room because of this compared to our MK1 Jazz.
4. Crosswind stability at motorway speed - This is a problem for all lightweight cars but it seems a little worse compared to our old MK1. When fully loaded with passengers our MK1 was actually reasonably stable whereas with our MK3 sport, it seems a bit more susceptable even when fully loaded.
5. Dash reflection on windscreen - On sunny days, you can see the textured plastic dash reflected on the windscreen which is quite annoying and sometimes distracts you. But we've learnt to live with it.
6. Driver seat, I get a slight backache with the seat after a long drive but doesn't seem to affect my wife so it might just be me.
Other than the above, we love everything else with the sport, the looks, the way it drives, the little gimmicks and so we plan to keep it for quite some time.