I had the iRobot Verro 300. It moves and has suction with just one pump so it always had problems going up my walls and up the very steep hill from 10 ft deep end, especially when using the very fine sand/silt bag when the pores in the bag began to get closed up from the silt, which, in my pool, is extremely fast, a few minutes, because we have extreme, extreme, blown in and carried in fine silt, some even smaller than 1 micron. Almost no pool filters can even filter that small size out. I'm hoping my new Pentair Quad 80, with cellulose media will do even better than my old DE filter. (Finally being installed tomorrow

) At any rate MOST people do not have the amounts of silt we have nor the steep incline from deep end. For most pools I think owner would be very satisfied with the Verro or other 1 pump robots. One can purchase an iRobot Vero on HSN using the Flex plan. There are three models, I think, but all are not always on HSN. BTW.... I'm pretty sure the iRobot Vero is a re-branded Aquabot.
I recently traded the Verro for an aged but well working old Aquabot. It has rubber drive treads like a tank. It was a fabulous trade for me especially as many of the common replacement parts are new. It has separate strong drive motor and big water pump that does an excellent job. It is slower moving than many of its new cousins so it doesn't stir up the fine silt very much. The water pump makes for much stronger suction than the Vero 300, too. It climbs my pool walls splendidly and it moves as well up the steep slope (and the walls) as it does in the shallow end.
Everyone is right. The robots can be very heavy. Verro 300, though, weighs less than my Aquabot. They are especially heavy when using the fine bag that has become lined with silt as it takes some time for the water to drain out of the bag.
The Vero and now the Aquabot has been a pool and wits saver for me when I can't, for what ever reason, run the main pump, which has happened several times. The robots circulate thousand of gallons of water per hour. The Aquabot and two submersible pumps pushing water through two big, recently purchased Slimebags have been the most of circulation/filtering I've have for several months and the pool is not covered. Some of my silt even goes through the 1 micron rated Slimebags. Many people here, as where you live, don't close their pools in winter. The electric cost of the robots is, also, way low compared to running pumps for the other cleaners.
I have a suction side cleaner that, also, works quite well, but not nearly as fast as the Aquabot, Verro, and the Polaris 280 with booster pump. It does the worst job, though, with leaves. Polaris is best, robot next, then suction cleaner.
All but the Polaris require time and effort to take out and put in the cleaner. Cleaning the bags on the robots are more trouble than the Polaris. Although I do have a big leaf trap canister for the fairly new suctions cleaner, I had growing concern about sending so much sand, much of which goes past the leaf canister, into the impeller of the pump. The big hoses on suction cleaners are a hassle to deal with if you are cleaning the pool daily. Maybe not so much if you do it once or twice a week. Storing the fat sectional vacuum hose can be an issue for many as they are not supposed to be stored wound.
I've had Polaris 280 pressure cleaners since they arrived on the market. It, to me is the least hassle of all and it does do the best with leaves and larger debris. It weighs a whole lot
less than many of the other cleaners and the water drains out of the bags very quickly so you aren't lifting the extra weight of water. Many people find the fine mesh sand/silt bag fine enough to capture their silt but most my silt just goes right through the Polaris sand/silt bag so I have had to resort to finer bags than are available on the market, with one exception. There are disposable Polaris bags, E-Z bag but cost is a factor if you have extreme amounts of silt as they can not be washed out and reused, like some "disposable" bags for other cleaners. I go through at least one per day with normal pool use. I'm making my own "disposable" bags now for Polaris; still in experimentation phase though.
Although it is best to take any cleaner out of the pool when children or pets, or even some adults are swimming my large and GIANT dogs have no problems keeping untangled swimming with Polaris or pressure cleaner hoses are in the pool. They just swim right over them. The best swimmer, though, has become tangled in the robot cord. I'm using the robot at night after everyone is finished swimming and dogs are kept out of that yard. But I do have to remember to take the robot out in the morning when I let the dogs out.
Hope this helps some. Take a few days observing how outside surfaces become covered or not with silt, sand, mud, pollen, etc. That might help with your decision.
gg=alice