I never use the 'proper' needle, just the right size. I have found that if I use a topstitch needle in ALL of my machines I have better results, especially embroidery. When I use a regular embroidery needle my thread shreads--the topstitch needle has a deeper groove and bigger eye hence less stress on the thread so less shreads and breakage. I just tried different needles on the fabric until I found what worked best for me. I also found that the stabilizer and the correct way to hoop was the key to great embroidery.
Here is a great place for hooping:
http://www.annthegran.com/cs/blogs/a...ne-6-2008.aspx
annthegran has lots of information.
Good luck!