Need advice on new 401(k) fund options

[Stone11]

My work is transitioning 401(k) administrators from Northwestern Mutual to Advised Assets Group and I need advice for which fund(s) are the least  bad.  I'm 32, am maxing my 401(k), and about 12-15 years away from retirement.  I'd like to replicate VTSAX as close as I can while keeping the ER as low as possible.  The fund choices are as follows:

Fund                                                               Ticker         ER
Great West Lifetime 2015 Fund                      MXLZX       0.98
Great West Lifetime 2020 Fund                      MXAHX      1.09
Great West Lifetime 2025 Fund                      MXFLX       1.02
Great West Lifetime 2030 Fund                      MXAUX      1.15
Great West Lifetime 2035 Fund                      MXLLX       1.04
Great West Lifetime 2040 Fund                      MXBEX      1.12
Great West Lifetime 2045 Fund                      MXRLX      1.05
Great West Lifetime 2050 Fund                      MXBQX      1.15
Great West Lifetime 2055 Fund                      MXXLX      1.06
Great West Conserv Profile II Fund INV         MXCPX      0.91
Great West Moderate Profile II Fund INV       MXMPX      1.04
Great West Aggressive Profile II Fund INV     MXAPX      1.21
American Funds Capital World G/I R3             RWICX      1.10
American Funds New World FUND R3             RNWCX     1.34
Great West International Index Fund INV      MXINX       0.71
MFS International Diversification R3               MDIHX       1.21
Templeton Foreign Fund A                              TEMFX       1.22
Great West Real Estate Index Fund Inv         MXREX       0.75
Invesco Energy INV                                        FSTEX        1.28
MFS Utilities A                                                 MMUFX      0.99
PIMCO Commodity Real Ret Strat A               PCRAX        1.53
American Beacon Small CP VAL A                   ABSAX        1.22
Janus Henderson Venture S                          JVTSX          1.19
Baird Midcap INV                                           BMDSX        1.08
Great West Goldman Sachs MDCPVAL FUND MXMVX        1.24
Great West S&P MIDCAP 400 Index FUND    MXMDX        0.61
Blackrock Equity Dividend A                          MDDVX         0.97
Great West S&P500 Index FUND                  MXVIX          0.56
MFS Value A                                                  MEIAX          0.86
T. Rowe Price Growth Stock Adv                   TRSAX          0.93
American Funds American Balanced R3        RLBCX          0.93
AllianzGI High Yield Bond A                          AYBAX           0.98
Blackrock Inflation Protected Bond INV A     BPRAX          1.02
Great West Bond Index Fund INV                MXBIX           0.50
Janus Henderson Flexible Bond S                JADFX           0.94
Oppenheimer International Bond Fund A    OIBAX           1.05
PIMCO Diversified Inc. A                              PDVAX          1.16
PIMCO Total Return A                                  PTTAX           0.86

I am leaning towards just going 100% into the S&P500 fund (MXVIX at 0.56% ER) but am also considering throwing maybe 20% at Midcap 400 (MXMDX at 0.61 ER).  Anyone have any suggestions or thoughts on these 401(k) options? 

[nexus]

If I were you (and I'm not), I'd consider going nearly 100% between:
Great West S&P500 Index FUND                  MXVIX          0.56
&
Great West S&P MIDCAP 400 Index FUND    MXMDX        0.61

Want something more conservative, add:
Great West Bond Index Fund INV                MXBIX           0.50

Typically conservative folks do something like 60/40 stocks/bonds or 70/30


VTSAX is going to be most closely replicated by a combination of MXVIX & MXMDX. I wouldn't bother with any of the other funds just because their ER are high.