Hello I'm new here, I have a question about linen. I am planning on stretching some large Linen Canvases and I'm trying to decide which brand and weave to go with. Im looking for something that is strong enough to stretch on a large 50 x 70 inch strecher and most importantly is without a lot of imperfections. Unprimed or clear primed. I know it's a smooth portrait linen I'm looking for but is there a specific brand and number linen you would recommend?