I'm applying for HPSP and am WL at USUHS. Honestly, I wouldn't solely consider the financial benefit of HPSP. It's been about 3 years since I started talking to recruiters and gathering as much information about HPSP and I've come to the conclusion that military medicine is something I WANT to do. Yes, the financial flexibility is a huge plus, but it's not worth it if you believe that you will be sacrificing things when you are paying back your time. For instance, from what I've researched, it is very common to do an intern year and then straight to service via a GMO tour. A lot of specialties don't get approval for "straight through" training, so the GMO tour after an intern year is a possibility. If you take the $20k signing bonus, then you owe another 4 years on the reserves after your initial 4 year (assuming you're taking the scholarship for all of med school) obligation.
What it boils down to is what you value and how you see yourself practicing medicine after training. The military will make you serve dual roles as a physician and as an officer, which I think is such a great opportunity. Everyone is different though. Considering how low Texas tuition is, I don't think you'd graduate with an insane amount of debt that couldn't be paid off within a couple years after residency. Just some things to consider. Congrats!