Welcome to GMAT Club and Congrats on your Admits!
Tech Product management is a very competitive field. You will need as much umph as you can get (which means networking, differentiating yourself, getting an edge somehow, etc). Just because you happen to be in Seattle, you won't be preferred for a job that a bunch of folks from Sloan and HBS applied for from East Coast. Good jobs have a lot of competition just like good business schools. Amazon hires a lot of ops folks (over 1,000 mba's were hired in the 2017 alone). I would really talk to the current students and ask for how many offers for jobs they have (from both McCombs and Foster).
I feel there is a big difference in rankings - around 10 spots. That has an impact on a number of items - size, class options, classmate caliber, professors, school pride, alum network responsiveness, etc. McCombs is a Top 20 school with a 250+ class size. That's enough to make it worthwhile for an employer to come on campus. You won't get as much attention in Foster, even though you are close by MS and AMZN. Having said that, a family member may help getting you plugged into a network and getting to know some MS and AMZN folks. (There is also Google, FB, Dropbox if they are still alive, etc). But Austin is also a strong tech community. Austin is a great city. You should definitely attend the admit weekend. It is not like typical Texas and really up and coming. The cost of living is much better than Seattle if you are comparing dollars. Unless you want to be in Pacific Northwest long term and you really like it and your family member can get you plugged in, I don't see Foster beating out McCombs.
Just one data point for you. Again, congrats on your admits!