First off, be weary of 'since inception returns' as these will vary widely - it's more accurate to compare returns based on the same time-frame. For example, a fund that was started in 2009 is going to have a much higher 'since inception return' than a fund launched in 2007. A more accurate comparison would be that of their 6-month, 1 year, and 3 year returns versus that of their benchmark indices.
Secondly, you're in a good position! The ability to use a self-directed brokerage account means free reign on which investments you'd like to use (including Vanguard Retirement Funds). But, even the option of a 0.32% MER target retirement fund as the alternative is excellent.
Feel free to post more information and ask any specific questions you might have regarding the individual investment options. Either way, it seems on the surface that you're in a good position regardless.