Re a wheeled case for your 15000, I tried the Janome molded case and did not like it at all. I found it exceedingly cumbersome to get the machine into it, and then there was no real room for anything else.
I do have the Tutto XL wheeled case and I will have to say, I Love it. I can get virtually everything in it (embroidery unit, in its case will strap on top). I use the Velcro ended, adjustable straps to anchor the machine in (criss-cross, then hook and pull the straps snug) then can insert my accessory bag (the one with all the feet) and the instruction book fit inside. My 6" x8" Snapware box of needles, scissors, pencils, screw drivers, etc fits in one of the exterior pockets on the end, and then there is still another end pocket, and a full length zipper pocket on each side. And a zipper pocket on the inside. Hoops will fit into the exterior zip pockets.
And, if you have the Babylock Ovation serger, it can be used for it, too. You do have to unsnap the back cone holder (the instruction book does tell how to do it)) and then it fits perfectly!!!
The Tutto case is not designed for air travel. It does have the spiffy Tutto feature where it can be "flattened" for storage, and the pull handle will also detach if needed.
Hope this helps...
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