If I had $30000 to invest  I would try to have as much bitcoins as possible quiclky because I believe in bitcoins.
The best way to have more bitcoins with fiat is to buy shares of mining compagnies earning bitcoins.

Hypothesis

• I WANT to risk my $30000
• I AM a real bitcoin believer
• 2014 BTC = $500
• 2015 BTC = $1,000
• My compagny will reinvest enougth to outpass de difficulty growth

Option 1 - Buy BTC & wait - I buy 60 BTC  ====>      2015 value : 60 * 1000 = $60,000


Option 2 - Buy Shares &  take dividends - I buy 60 shares 1BTC each - Dividend 50% per year
                              2015 value :
                                     Dividends  2014 :  15BTC
                                     Dividends  2015 :  30BTC
                                     Shares      : 60BTC
                                        Total           60+30+15 =105BTC *$1000 = $105,000

And on top...if we are 2015 and BTC = $1000 the value of my shares will be much more than 60BTC. May be 100 I think so it is more $145,000


Option 3 - Buy Shares & reinvest dividends - I buy 60 shares 1BTC each - Dividend 50% per year
                              2015 value :
                                     Dividends  2014 : 15BTC ==>reinvest
                                     Dividends  2015 : 37.5BTC
                                     Shares      : 75BTC
                                        Total           75+37.5 = 112.5BTC * $1000 = $112.500
And on top...my shares worth more 75 ==>130... so may be  $167,500