We've had our MX8 for roughly a year.
Hmm. I guess we got lucky, as ours works pretty much beyond expectations, particularly after getting our cleaner line unclogged and working properly... and getting a Hayward in-line leaf basket. We used to have this pool guy who was kind of a dufus and I always wanted to get rid of him. But, he was responsible for vacuuming the pool each week (along with chemicals), and our neighbor's trees are always dumping debris in the pool. Fortunately, after getting the system dialed in (which really took about four months because of unknown cleaner line issues), it works to keep the pool surface quite clean.
Two things it does not do a good job of: cleaning the steps and cleaning the attached spa. Now, a robotic cleaner might do the former, but there's not much to be done regarding the spa. So, occasionally, I'll have to vacuum the spa and steps (maybe once a month or so). The previous problems regarding the cleaner getting stuck due to leaves have been mostly fixed by increasing the vacuum/flow. However, occasionally (maybe every couple of weeks during periods of high leaf droppage, once a month otherwise), it will get stuck and needs to be cleaned out. I actually take the unit apart to thoroughly clean it about once every three months or so, and sometimes the rubber cat-tracks need to be seated properly. I consider this all normal maintenance and it really doesn't bother me. If I had a mesh cover over the pool, I might have a different take on this.
I have considered going with a full-on robotic system, but there are a couple of things holding me back. First is the price. Since our MX8 is working fine for most things, and I don't mind occassionally vacuuming the stairs and spa, the price differential for a robotic cleaner is too great. If I were to get one, I'd likely purchase one with a remote so that I could have all the features. Those are pretty expensive relative to the MX8. The second concern is repair issues. The MX8 has many fewer parts and these are readily available at local and web-based vendors for reasonable cost. Given that water and electronics don't mix very well, there are bound to be expensive issues with robotic cleaners. I'm sure some brands are better than others, but I have read about a few horror stories. Failure of my MX8 means purchasing a couple of cheap parts that are user serviceable, but failure of one of these robotic units often means a trip back to the manufacturer and a likely expensive repair bill.
I think my point is that you need to be realistic about what an inexpensive suction side cleaner can do. If you want absolutely the minimum maintenance, a robotic cleaner is probably the best move. A suction side cleaner will cost much less, but will require more maintenance, and will also need to be dailed in with each pool.
