Ok, here I my thoughts on the Marathon + (28mm) based on about 2wks and 200 miles of use so far. So fair to say they probably haven't broken in yet.
It's also fair to say my experience is fairly -ve at the moment, BUT, I remember changing from Michelin Pro race 2 tyres to Gatorskins and having similar -ve thoughts on changing (never thought gatorskins were dangerous though), I guess you get used to tyres?
General feel:
They feel more cushioned (maximum pressure of 100psi), give a softer ride. I actually like that for commuting. It's nice, less bumpy.
Because of the above you really can feel the drag, it is a real effort to push them along, I don't like that
On the Friday before putting them on it took me 1hr2mins to do my commute from the Ferrytoll, on the Monday morning 1hr10mins !! Been at that for the last fortnight, legs will probably adjust over time and I'll get back to about an hour, but bejings they are hard work.
Cornering:
When dry not to bad, although my bike all of a sudden sounds like a mountain bike cornering, rrrrrrrrrrr. I don't like that.
When wet I have no confidence in them at all, I was trying to think of a word to describe them and couldn't, Dave called them "edgy" and I think that sums them up pretty well they feel horrible cornering.
The downright dangerous:
As alluded to above wet cornering is bad, but worse still, things that were not an obstacle before suddenly are now! Two examples, the textured paving on the Meadows, never a problem before for me even in the wet. Even in the dry the bike now seems to 'slide' through them rather than roll. I understand others pain regarding this paving now, it really is scary!.
Joining tar on road (where road has been dug up and relaid), never used to notice it before, just rolled over it if changing direction. Any change in height in road surface results in tracking (is that what it's called?). You try to change direction, the wheel is at an angle but you just continue to slide in whatever direction the raised bit is going, really really don't like that. When your front wheel does change direction you then have the same nonsense a second later with the rear, at least a rear wheel skid is easier to control.
I know others don't seem to have any issue with them, maybe I should have gone for 32mm instead of the 28mm? But I have heard lots of people on here complaining about issues (textured paving etc) that I never experienced before these tyres.
Overall though, if my time gets back to about an hour, and the punctures stop I'll suck it up and keep using them for commuting (maybe wider ones though). If my time doesn't improve then 18-20mins a day extra on the bike is just not worth the 20mins once a month it takes to fix a puncture, I'll go back to gatorskins.