I've quilted several large queen quilts on my Juki TL2200 (same as the 2010) and will be quilting a 120x120 king shortly. 1/2" channel quilting with your walking foot should be very doable - much more so if you're not on the diagonal. I agree with starting from the center and taking it slow expecting to reposition your quilt a lot. I also have a large table which helps support the quilt and reduce the drag. I've always had great results quilting on my Juki - FMQ or walking foot - just take your time
Look forward to seeing pics of your finished quilt!