I've been on a Drytac JM44 for the last dozen or so years, use it daily for mounting and laminating. I'll flood coat materials (Kapamount, Forex, sometimes dibond) straight off a roll of self wound adhesive (sometimes, with gloss prints, I'll use facemount adhesive, but I tend to avoid these orders).
If I were doing canvas, I'd consider a heated top roller for lamination, but I only print canvas for a couple of artists who do their own stretcing. I don't have spraying facilities.
If you're looking to laminate prints, I'd definately get a motorised laminator - leaves you with a free hand to remove dust from prints.
My next laminator will likely be 60", have heated top roller, and have a motorised take up reel for roll to roll work. We now do enough banner printing and self adhesive vinyl to make this worth while. It'll also open up the option of laminating Phototex, which i think we'll need as we're aqueous printing.
We're a film processing, scanning, exhibition printing and mounting, but not framing studio.