O.K. jumpy - the direct answer is that they do indeed take DECs.
The warnings are equally correct. There are loads of warnings in different threads on this site, which you really should read with care.
However, while Ryanair are doing a good job of keeping it quiet, they are increasingly short of pilots and, for example, are currently cancelling leave for pilots in Stansted, etc. So, you might be able to get yourself a good deal (which they will change - reduce - when they can).
For example, according to the REPA site, they are still doing their "reduce pilot cost thing" at, for example, the new Liverpool base where they have apparently reduced pilots salaries (quietly) in line with the "local cost of living index"! So, never forget, all is not what it seems in Ryanair!!! As they are being caught out at this game, they might change their minds.
So, in summary, make sure you see your contract before you start (harder to do than you might think). I wish you Good Luck, since everyone in Ryanair needs a bit of that.