Okay, my two cents on the subject.
I have 5 different machines - 3 are set up and ready to go all the time. My Pfaff Expressions 2.0 is constantly used, My Bernina Deco embroidery machie and then my next favorite machine is my 20+ year old Singer Serger. This is my busy time of year as My DH & I do lots of craft shows and I find My serger is indespensible. Yes, I use it on the many clothing items I make but I also use it on all of the quilts I make, such as baby receiving blankets to edge them, log cabin style quilts using the "quilt as you go" technique, strip piecing quilts once again using the "quilt as you go" and for trimming up the edges of all my big or small quilts before I put on the binding. It makes all my pieces look all that much better. I would definitely take a few days and really play with the serger - it's a blessing when it comes to ruffles, too! As many before me have said it all depends on what you like to make and create. My two other machines - Janome for traveling to workshops/retreats/classes and an old BelAir for heavy canvas and denim work.