What is easier to one person is not necessarily easier to another -- that might sound cryptic so let me try to explain the differences between the exams so you can decide for yourself.
The SCJP exam has for a long time been about understanding the core concepts, learning a few (but not too many) API details and spotting key things like difficult-to-spot compilation errors, operator precedence, deadlocks, more recently generics etc.
The SCWCD 1.4 and earlier exams were heavily biased towards candidates recalling API and web.xml details, so memorising those parts of the specs was guaranteed marks. Of course there were other questions based on spotting compilation errors too, but none so tricky as in SCJP questions. In some ways this isn't a surprise: the Web tier is so complicated that all its servlet, filter and custom tags functionality is exposed through APIs alone, so knowing the classes and methods is important.
The SCWCD 5 exam has moved towards more "performance based" questions -- so while you need to know the APIs, you also need to be familiar with how it all fits together to actually build an application. While I haven't sat this new exam myself, I imagine a question which previously focused only on the RequestDispatcher may now focus on both a servlet and JSP and require you to know how the RequestDispatcher works to get between those two resources, for example. Anyone having sat SCWCD 5 will be able to enlighten us further (without revealing any actual questions).
Personally, my memory isn't fantastic, so I prefer questions which challenge my ability to write decent code and not remember perfectly the API. After all, when on the job, I have the API or IDE
at hand to help me! Others find memory recall easier, though that's then no excuse for not having a solid understanding from which the rest then follows...