Do you invest in your tsp?
Yes, I max out the TSP. I prefer the Lifecycle funds; they are similar to Vanguard Target Retirement funds where they do automatic rebalancing and also update the stock/bond mix as you get close to the retirement date. The military does not match your TSP contribution because you have the retirement option as well. Most people who retire from the military can live just fine on a military retirement, especially if you have your house paid off. Because we move a lot I want to be able to save cash for buying my house.
The problem is that the TSP is pretty much identical to a 401(k) so you are limited in your ability to pull that money out before 59.5 years old. So while I save in my TSP and my IRA I also put other money aside to be my dedicated "house" money for when I retire from the military. I am currently putting that money in two Vanguard mutual funds - Total Stock Market Index fund (VTSAX) and Total International Stock Index fund (VTIAX) in a 70/30 ratio. I am aggressive so I am 100% stocks and am 14 years away from retirement so I have some time.
I recommend you open an account with Vanguard. Your mix of stock/bonds will be based on your timeline. Essentially if you want to have that money in the next five years then you really shouldn't put it in the stock market - just put it in a municipal bond fund, CDs, or money market account.
Let me know if you have any more questions.