I've been working at Transpac for about 6 months now and would be happy to talk with you. PM me and I will give you my phone number.

The position absolutely will not be part time at Transpac for long. basically, the next time a class starts (every few weeks) you will be assigned 4-5 students and will work more than you could ever want. You can always pick up randoms on your weekends if you want more flight time! Though you won't get paid any more for doing that.

I instructed at a very small school and a local FBO for about a year before Transpac, and there are advantages to each situation.

Transpac
-Steady flight hours: 80-100 per month
-Steady pay: Salary
-Large fleet: Few cancelled missions due to resource availability
-Amazing flying weather
-Great dispatch and scheduling: In my mind the biggest advantage of working here
-Networking: Previous hiring relationship with all the regional carriers, pipeline with Eagle and Skywest, and CFIs leaving to the regionals all the time
-Advancement: if your goal is to stick around and such you can do Ok here

Independent
-Set your own schedule: a double edged sword as you don't get paid to be a scheduler and dispatcher
-Higher hourly pay

Transpac as well as other flight schools have been discussed a lot on the forums and a quick search can reveal some information. A lot of things have changed here in the last few years though, so read older stuff with a grain of salt.

Ultimately it depends on your goals. If you want to go to the regionals Transpac (or other "name brand" school) is probably the fastest way to get there.