Getting the best fitted mudguards for a standard road bike I'm quite new to cycling and soon I'll experience my first winter cycling, thaמkfully I live in quite a dry country so we don't have a lot of rain.

I've read all about the clearence issues of regular full mudguards with most road bikes but I'm still quite confused about what I should order.

I've found these two:

Raceblade Pros

and 


Raceblades

I have a Ridley Fenix Classic and it should have the regular tire clearance that most road bikes have (I have a 23mm tires).
I know the general guidelines but would like to get help about what mudguards will surely fit my bike.

*Or maybe it's very hard to guess what mudguards will fit by ordering online and will be better to just find a big store that will sell those (probably'll be a bit more expensive)?
Specific product recommendations are off-topic here.  With regard to bike fenders, though, there are several things to consider.  Fit is perhaps the most important -- the fenders must not only fit but provide reasonable clearance for the tires you may be using (keeping in mind that lugged tires need much more clearance).

After that you need to consider the ease/robustness of the mounting system, the robustness of the fender as a whole, and the coverage provided.

With regard to clearance, one thing you need to do is figure out the actual diameter and width of the tires you will be using and compare that to the fender specs.  The couple of times I've bought fenders online this has worked for me.

Added:  One important thing to consider is toe clearance on the front fender.  Usually any fender will result in some minor toe clearance issues, but there's a difference between your toe occasionally brushing the flexible plastic fender and your foot jamming against an oversized stiff metal fender.

And another thing:  If you have plans to ride in the snow then either avoid fenders entirely or get ones that are easily removed.  In the right connditions snow will quickly become jammed between tire and fender and make you grind to a halt.