investment options are not as vast as the larger low-expense houses (vanguard/fidelity) and thus they suffer on some of the expense ratio comparisons (0.18 vs 0.29 for example on an S&P 500 index).
usaa has met my standards of customer service at every chance, and i'm willing to lose a few thousandths of a percentage point on my mutual funds each year to get their service.
This is very misleading. USAA doesn't even come close in comparison to Vanguard for investing in index funds. The index fund you mention is one of only 3 that USAA offers compared to the 100+ offered by Vanguard. The rest of USAA's funds are actively managed with expense ratios > 1%. Also, you will be forfeiting much more than "a few thousandths of a percentage point each year" even with the S & P 500 that you cite instead of taking the Vanguard alternative. See below for examples.
For example (S&P 500 Fund):
Amount invested : $10,000
Annual return : 7.00%
Projected expense ratio is : 0.29%
What if the expense ratio is : 0.18%
Your investment returns over 30 years will be $2,203 more if the actual expense ratio is 0.11 percentage point(s) less than the projected.
Projected expense ratio
Actual expense ratio
0.29% 0.18%
Net market value after Difference
1 year $10,671 $10,682 $11
5 years $13,836 $13,908 $72
10 years $19,145 $19,343 $198
15 years $26,490 $26,902 $412
20 years $36,652 $37,415 $763
30 years $70,170 $72,373 $2,203
And...
Amount invested : $10,000
Annual return : 7.00%
Projected expense ratio is : 0.18%
What if the expense ratio is : 1.00%
Your investment returns over 30 years will be $14,938 less if the actual expense ratio is 0.82 percentage point(s) more than the projected.
Projected expense ratio
Actual expense ratio
0.18% 1.00%
Net market value after Difference
1 year $10,682 $10,600 ($82)
5 years $13,908 $13,382 ($526)
10 years $19,343 $17,908 ($1,435)
15 years $26,902 $23,966 ($2,936)
20 years $37,415 $32,071 ($5,344)
30 years $72,373 $57,435 ($14,938)