I recommend purchasing sewing machines from your local retailers rather than on-line, if at all possible! They're the ones who will be able to sit down and review the machine w you, auto threader and all.
We had a super quilt shop open last year (The BOLT in CT) that's a JUKI dealer. They weren't around when I bought my JUKI years before (on the internet) but they were kind enough to review w me how to use the needle threader when I first visited the shop, and we started talking.
Here's their youtube link for the JUKI 2010Q automatic threader.
http://youtu.be/SZxiEQ8wIlI
Regarding the TL2010: it's truly a semi-industrial machine designed for quilting-related processes. The DX series, like the F series, are home sewing machines and (almost) do it all. They are all, imo, great machines, w different purposes overall.