I do all of mine this way, too - for me it's actually quicker than driving to the tailor, having them measure, drive back to pick them up, etc.
One thing I found is that over time the tricky hems tend to curl back up to the outside almost like a tiny cuff. To prevent this from happening, I do two things. First I tack stitch the inside zigzagged edge to the leg in about three places with one tiny hand stitch only - you can't see it at all from the outside (be sure to match your thread to the wash of the jeans). I also take a hammer and pound on the vertical seams where they meet the original hem. There's so many layers of denim that it wants to fold back up there especially. No harm done to the jeans, just sort of "works" them so that they'll lay how you want.