Hello gorgeous! Some time ago I noticed that some of my brushes (made of natural bristles) started to lose their shape due to extreme fluffiness. I have read a lot information about Sigma Dry`n shape brush roll but I think this one is quite expensive ($29) and also I own only 5 Sigma brushes, so I am not sure that it is going to suite my other brushes. So I decided to purchase "Brush Guards" (1 m of synthetic tubular net) (by the way it costs only 1.5$ and shipping is free (EBAY).
As I mentioned basically this is just a synthetic net. But it saved my brushes!
Sigma F25 brush dried without brush guard:

and using brush guard:

Looks totally different, right?

Now MAC 130 duo fiber dried with brush guard (Perfect shape!)

And here you can see how brush guards (upper) actually look (together with an alternative):

And brush guard on my finger:

And alternative called "Elastic tubular net bandage":

And the packaging:

Sigma F10, Sigma F25 wearing brush guards and MAC 130 wearing bandage:

And smaller brushes (MAC 217 and 2 Sigma E25 )

Brush guards are must haves for bigger brushes, but unfortunately they tend to slip off from smaller brushes (like eye brushes) stored in vertical position. Thus for eye brushes I would recommend to use "Elastic tubular net bandage".