It really is not that messy. As with anything, you have to clean up after yourself, but it is by no means overly messy. I wipe the froth wand off, run some water out the group to rinse off loose grounds and give it a quick wipe with the damp towel. One swipe across my work area with the dish towel and it is clean. Then I do a
once a week backflush and wipe down of the equipment to keep it nice and shiny. About 20 minutes of leisure work on a Saturday morning at most.
I would think a doserless grinder would produce more displaced grounds than a doser would. I use a mushroom brush to clean my MM hopper, doser and chute. It is made for brushing dirt off mushrooms. Moderately stiff bristles (much softer than acid brushes I have used) and the best part, it is wood. Just in case I stick it in the machine before the burrs have spun down. I am less worried about wood contacting the burrs. After all, coffee is just a woody seed that has undergone a controlled burn. The bristle tuft is a little longer and much thicker as well. I also had one in the kitchen cabinet when my Mazzer arrived, so that is what I used.
I do not have first hand experience with the Expobar, but Worldman (Len) has one. He invited me to his home while I was in Pittsburgh on business and made several drinks from it. Seemed like a nice machine and a smaller footprint which is important if you are short on space. I also looked for a machine that got a
'Looks nice' from the wife. It is much easier if the significant other likes the appearance. She accepted its presence in the kitchen with much less effort from me.
I have no issues with Whole Latte Love, in fact, my Isomac and Gaggia came from them. I got my grinder from Chris Coffee. Just a plug for the folks that pay to support HB.
Whatever you final decision, a good peace of equipment that is properly maintained should last for years.