I've been using Superiors' Treasure thread on my PTTD quilt (
http://www.superiorthreads.com/shop/category/treasure/products/) and at first it was a little hard for me but not all because of the thread though. I haven't hand-quilted in years so I had to get my 'groove' back. The thread is thicker so I also had to locate the perfect needle that worked well. The needle that has worked well for me is Jeana Kimball's quilting/between needles (
http://www.jeanakimballquilter.com/store/betweenneedles.html). I bought the variety pack because I wasn't sure what size I would be able to work with and the number 10 needle won out. It's small but not too small and the thread goes through the eye of the needle. The thread would not go through the 11 or 12 needles and honestly I cannot even see the eyes in those higher sizes.
If you do try this thread, it is a little wiggly when you unwind it from the spool but it stitches well and shows up nicely on the quilt. If you 'do not' want your thread to show, I would not recommend using this thread as it is thicker and I believe designed to show your handwork. I figured if I was going through all this work, I wanted to be able to see my stitches.
Also, I cannot recommend highly enough my TJ's quick quilter --
http://www.tjsquickquilter.com/ -- I have not one prick on my finger that is underneath my quilt, and my stitches are getting more perfect ever day. The longest I have hand-quilted in one sitting is 2 hours and the only reason I stopped is because I needed a potty break not because of fatigue.
Have fun and enjoy the process.