I assume up to a max, which you are probably doing. Even over and above that amount it still makes sense to contribute there due to fees. 31K in a MF @ 2% is 620 dollars in fee's each year. That's a decent savings each year to hold company stock. A TFSA in one holding likely isn't going to give you diversification issues since generally they arn't paticulalry large in comparision to most people's RRSP's, DB or DC pensions, real estate etc holdings Of course.

Of course all the saving on fee's won't help you if the company is a total dog.

Company is decent. Stock is okay. I'd like to say I have a diverse portfolio. In fact I'd like to say I have a portfolio.