I installed this Vacu Maid system in 1996, and it was challenging since this was a retrofit to my home. I installed two outlets per floor (3 floors), and was able to hide the entire installation in closets and existing chases in my home. The installation was a good experience since it allowed me to prepare for the later work where I would be wiring Cat 5 and RG-6U to every corner of the house.

Compared to a regular filter vacuum, this cleans better, quieter, and all dirt is ejected from the house. The system is lighter and more maneuverable. Since it has no substantial filter, there is no obstruction to the unit's power. 

I decided to spring for two sets of electric powered sweepers. I also bought the turbine powered stair sweeper. It is a hand held turbine brush. Great for cars as well. The air turbine units are more prone to clogging (all dirt needs to pass thru the vanes of the turbine), and reduces power a little. 

Some pointers for installation:

• The only place a tight 90 degree turn should be used is right behind the vacuum receptacle. In this manner, the tightest turn in the system is right where you can reach the obstruction (after you remove the vacuum hose). The rest of the system should use sweep 90s and sweep Tees. Thus if you vacuum up a pencil, it will get stuck right at the receptacle, and you can remove it by unplugging the hose.
• On horizontal runs, do not connect to it from below. Dirt travelling in the horizontal run can drop down into the connecting tube. A friend of mine did not do this, and while vacuuming glass shards, had them drop into the connecting tube, filling a vacuum outlet with glass.
• Design the system such that you do not have to turn the pipe upwards (dirt only flows downwards).  The only exception is at the 90 right behind a receptacle. The upward turn can cause plugs. If you do need to turn upwards, install an access cleanout: a sweep 90 and a plug.

• May 1996 - System installed.  Cost of the system: 
• 250 - main motor 
• 150 - pipes and fittings 
• 300 - toolkits, two hoses, two powerheads, one stair head 
• 700 - total
• December 2004 - replaced drive belt on Sweep 'n Groom II powerhead (belt is part number 36995, same as 52201C) at Eureka's on-line web site.  Other than that, the system has been trouble free.
• May 2010 - Bought a used Sweep 'n Groom unit for $40 shipped.  I used it for parts to replace the case of my powerhead which has been damaged due to many years of use.  New units are available for $130 shipped on Ebay.
  
• August 2010 - Found an advertisement on Ebay (seller id: storefront-22) for a replacement sweeper motor made by Lamb Ametek.  I think the Eureka part number is 118154-54, and the Lamb Ametek number is R5409-33.  The price was $40+$5.  Also available here.
  

Replacement motor.  Click for full size.

• December 2012 - Inspection of the small turbine powered sweeper shows turbine blades show some damage from years of use.
• January 2013 - Bought another used Sweep n Groom head on Ebay for $25+15, and this has the clear plastic front for an internal headlight.  Due to frequent bumps and vibration, the lights I have had blow out quickly.  I added a mod to put 6 bright white LEDs to replace the filament bulb.  They are powered by a tiny 12V switching power supply rated for 300mA.  Three lights are in series, and two strings of these put in parallel.  I then use a 10 ohm resistor in series with all this.  Total current is 100mA (two parallel strings).

• March 15 2021 - 25 year mark.  Added a vacuum gauge right at the motor unit.  It was purchased from Grainger.com for about $11.  It was added by drilling a 7/16" hole that I widened a bit and then threaded the gauge into the hole.  With no air flow, the developed maximum vacuum is -8.5 inHg (about 116 inches of water or -4.2 psi).  I had just cleaned the canister and filter a day before.  With one of the hoses attached to top floor outlet, the vacuum level was -4.5 inHg.  So if in the future, the motor runs with less power (due to a filter obstruction), I may be able to tell by a lower vacuum.

• February 2025.  Changed belt for the upstairs power brush.  The belt has an Inner Dia. of 65mm and a width of 16mm.  The model number of the power brush is EP210 (aka Supergroom II / Cen-Tec CT12DXL).  Parts use the model number as a prefix and their own designator as the postfix.  For example, the belt is part number EP21010.  Exploded view is here, some care instructions are here.