I have both drawplus 5 and xara designer pro X

if you want to work in vector the xara products are far better IMO

if you want brushes then drawplus is more flexible and a lot easier to use for these, although they are in the main bitmap based - they were the reason I bought drawplus, along with its's equivalent of the xara shape builder and eraser tool

[at the time I bought drawplus5 xara did not have these last two tools, now it does, although you do have to buy the pro version of xara to get both, unlike serif]

the screen rendering in xara is far better than in drawplus 5...