What yarn are you using? Maybe someone here has felted it and will know about how long it takes...
Personally I have felted Paton's SWS and it goes fast. My booga bag went so fast that it is barely big enough to hold my wallet !! I went down with a booga and when I came back upstairs the hubby said - that's cool you knit a change purse. The ER was able to save his life.
I've also felted Cascade 220 (personal favorite) and most times it takes just about a full cycle. Some stuff I've picked up at local fiber festivals is really unpredictable.
I fully expect the hubby and I to have a HUGE fight when we move and I tell him I'm never getting rid of my top loader. We can get a front loader for the effeciency etc, but the top loader is paid for and my first choice for felting and I still have about 100 pairs of felted clogs to make.