Hi Cathal,
First of all, Congratulations for passing Master Developer exam!
As you might be aware, there is no
assignment for web component developer exam, and it is just an objective exam.
Given this, in my honest opinion, WCD exam is simpler than Master Developer exam.
Yes, I took more time for WCD exam, but that was because I spend hardly 1-2 hours a day, and I had zero background of
Java Enterprise Edition.
Syllabus is little big compared to SCJP/OCJP, but since you've cleared both
SCJP and Master Developer exam, you have a good idea about difficulty level of SUN/Oracle.
So, don't worry. Once you understand the basics and do some hands-on, you'll feel comfortable. If one works dedicatedly towards this exam, then I feel it should take less time for WCD than OCMJD.
All the best! (and yes, do
not forget to refer head first
servlets and
jsp - its one of the best book - especially if you do not have any background).