I had to buy a "laundry center", rather than separate machines or stackable, due to the very small space for my machines.  I resisted the idea, because I had a perception that these laundry centers wouldn't do a good job, or the capacity would be too small.  I was wrong!  These machines are huge inside and do a great job of washing and drying!
I had my local appliance store deliver and install, which seemed quick!  (Sorry I can't speak to the ease of getting these installed.)
My only complaint is that when the washer starts up, it goes through this cycle of filling the tub, during which the water shuts on and off, on and off, quite violently.  My pipes make a huge noise which is making me worry about potential damage being done.
Otherwise, it runs really well.  The 'normal' wash cycle takes about 45 minutes.