I've been at a "large training vendor" for about a year now.....I think it's a great job. The money is decent, the schedule is generally good, usually most everyone is happy. Just like every job of course it has it's 'pros' and 'cons' but overall it's the best aviation job I've ever had. After having the opportunity to 'travel and see the world's most exotic locales' in a variety of corporate jets it's very nice to be at home every night with the family. I don't work holidays and if I need a day off for something I can always get it - even with short notice. Heck, I haven't even been working weekends lately. The bad side is that I don't get to fly.
As far as training, how it works here if you're not typed in the airplane you're going to teach - you go thru an initial as a client to get typed, you then go thru a recurrent as a client (with no checkride) and then you start getting qualified as an instructor in the 4 major areas - recurrent sim and ground and initial sim and ground. This can take some time as you usually observe say recurrent sims and then you 'practice teach' recurrent sims with another instructor then you teach it by yourself while being observed by a qualified instructor then you're signed off to do recurrent sims. There is also a bunch of other misc garbage you have to do - a company 'indoc' of sorts, the TSA training, etc. It's a very long and drawn out (and often frustrating) process. Usually at my center you get qualled to do one thing (usually recurrent sim first) and do that for a few months then start working on the other stuff. From Day 1 to fully qualified can easily take 3 to 4 months plus depending on the center's needs and styles.
We've been hiring a bunch of folks here - you may be one of them - PM me if you want.