The actual difference between that of a DC39 and a DC39i only comes in the fact that the DC39i  is provided with an extra accessory (clarified in the 'difference in accessories' section below) as well as the minor issue of a 'skin' colour difference (whereby the multi-floor standard version comes in the classic and iconic Dyson yellow whereas the 'independent' comes within a mesh of silver/red). Apart from these two factors, everything else remains the same i.e the DC39 and DC39i has the exact same specifications (e.g. size, weight, cleaning suction power) and practicalities (e.g. same cord length, bin capacity) -- they are the same vacuum model.

(Note: for quick details of the difference, head to the quick summary section below at the bottom of the article, detailing the varied attachments you get with the all the versions of the DC39).

Now just a quick overview of what aspects remain the same between the DC39 and DC39i i.e a look at the actual vacuum model itself. So firstly, they will obviously have the same cleaning performance -- in the fact that they are both fitted with the unique and advanced Dyson Radial root cyclone technology that allows them to essentially produce powerful centrifugal forces that allows the DC39 to suck up microscopic dirt particles (as small as 0.5 microns) as well as prevent it from loss of suction. Moreover, the fitted motor enables the DC39 to produce a huge 280 Air watts, making it the most powerful suction vacuum cleaner in the entire Dyson range and thereby probably the domestic vacuum market (certainly within the given price range, anyhow). 

Dyson DC39 Multi floor canister vacuum cleaner
Amazon Price: $449.00 Too low to display Buy Now
(price as of Aug 8, 2013)

With regards to mobility as it is one of the only cylinder vacuums to be fitted with the new 'ball technology' it makes it (especially compared to your standard rigid wheeled cylinder vacuum that has to be dragged back and forth to get around tight gaps and corners) incredibly easy to manoeuvre, allowing you to essentially turn on a singular dime (although if you haven't used a vacuum with the ball mechanism, it may take you a short while to get used to) -- only weighing in at just under 7.5kg (which for a vacuum of this size: H:50.7 x W:36.8 x D:26.1 cm, is actually pretty light). Moreover, the practical features it offers tend to lend itself to those who have the larger home whereby it features a huge bin capacity of 2 litres, a cord length of 6.5 metres with a max reach of 10 metres.

Difference in Accessories/Attachments

As stated in the 'introduction' the difference between the DC39 and DC39i comes in the simple fact that they are encompassed with varying accessories (as well as the standard version coming in yellow and the independent in red/silver). To go about explaining the differing accessories it is best to start with the standard version -- the DC39 is fitted with both a combination tool (which is essentially a crevice tool that allows you to vacuum tight/awkward gaps/areas as well as incorporating a brush nozzle to allow you to 'power' dust) and a stair (upholstery) tool -- both these tools are pretty much your standard accessory set -- that tends to comes with every Dyson vacuum purchase.

Then where the DC39i differs is simply: not only does it come with the tools that the standard model has (i.e the combination tool and stair tool) but it is provided with one additional attachment which is the Dyson stiff bristle brush. This attachment helps allow you to remove dug-in tough dirt stains (usually within soft flooring such as carpets) by providing a popping motion to 'flick out' the dirt which can then allow the dirt to be easily sucked up through the vacuum and straight into the DC39's bin. This is essentially the only factor that differentiates a DC39 and a DC39i -- that the latter comes with the additional Stiff bristle brush (and of course the colour change).

Dyson Stiff Bristle Brush
Amazon Price: $19.99 $14.00 Buy Now
(price as of Aug 8, 2013)

You should note however that this 'brush' attachment can actually be bought separately (e.g. see above on Amazon) therefore if you can't locate a nearby independent retailer that has the DC39i in stock, you can simply purchase the DC39 standard version and then the stiff brush and you would essentially have the DC39i package (apart from the DC39i's skin colour). If you have reasonable access to both (and you want the additional attachment) then you should just do some quick maths -- on which is more expensive the DC39i or the DC39 price + stiff bristle brush and see which works out cheapest (in theory it should be the DC39i, as you are purchasing them as a bundle -- which should hence be relatively discounted).

Dyson Tangle Free Turbine
Amazon Price: $69.99 $44.00 Buy Now
(price as of Aug 8, 2013)

In conclusion, the Dyson DC39 and its actual specifications/features/practicalities are all identical i.e it is the same vacuum model, all that has changed between that of the DC39 and DC39i is the addition of the stubborn dirt brush tool (to go with the DC39i) as well as the change in vacuum's 'skin' colour. So depending on what version of the DC39 you get ultimately depends on the respective price tag of each as well as that of the accessories and your 'preference' for them.

A final quick summary of the DC39 Vs DC39i Vs DC39 Animal Vs DC39i Animal with regards to what accessories come with what specific version.

  • DC39 (Multi-floor): Combination Tool, Stair Tool.
  • DC39i (Multi-floor): Combination Tool, Stair Tool, Stubborn Dirt Brush.
  • DC39 Animal: Combination Tool, Stair Tool, Tangle-free Turbine Tool.
  • DC39i Animal: Combination Tool, Stair Tool, Tangle-free Turbine Tool, Stubborn Dirt Brush.

If you have any questions, remarks or concerns regarding any of the versions of the DC39 or about the actual comparison article itself then please be sure to leave them in the comments section that you find just below and I will be sure to get back to you as soon as possible.

Dyson DC39 Animal canister vacuum cleaner
Amazon Price: $499.00 $404.19 Buy Now
(price as of Aug 8, 2013)