Depends on what kind of risk you're willing to take. Earlier this year I decided to play a bunch of these things to clear a bonus and after a couple of hundred games I wrote a quick and dirty simulator to try to get a feel for what I was in for (and for fun). I used to play around with this thing a lot.
Code:
Gui, Font, S14 CDefault, Verdana
Gui, Add, Text, x116 y10 w330 h20 , Double or Nothing SnG Simulator
Gui, Font, S8 CDefault, Verdana
Gui, Add, Text, x106 y60 w20 h0 , Text
Gui, Add, Text, x26 y60 w140 h20 +Right, Bankroll (in buyins)
Gui, Add, Text, x26 y80 w140 h20 +Right, ITM percentage
Gui, Add, Text, x86 y100 w80 h20 +Right, Entry fee
Gui, Add, Text, x76 y120 w90 h20 +Right, Rake
Gui, Add, Text, x56 y140 w110 h20 +Right, # if games in set
Gui, Add, Edit, x176 y57 w80 h20 vBRM , 50
Gui, Add, Edit, x176 y77 w80 h20 vITM, 55
Gui, Add, Edit, x176 y97 w80 h20 vEntry, 1.0
Gui, Add, Edit, x176 y117 w80 h20 vRake, 0.1
Gui, Add, Edit, x176 y137 w80 h20 vSetSize, 1000
Gui, Add, Text, x56 y160 w110 h20 +Right, # of repetitions
Gui, Add, Edit, x176 y157 w80 h20 vReps, 100
Gui, Font, S14 CDefault, Verdana
Gui, Add, Button, x326 y80 w110 h60 , Go
Gui, Font, S8 CDefault, Verdana
Gui, Add, Progress, x51 y220 w410 h20 vMyProgress , 0
Gui, Add, Text, x66 y280 w100 h20 +Right, Starting bankroll
Gui, Add, Text, x66 y300 w100 h20 +Right, Busted
Gui, Add, Text, x26 y320 w140 h20 +Right, Best run
Gui, Add, Text, x6 y340 w160 h20 +Right, Worst run
Gui, Add, Text, x46 y360 w120 h20 +Right, Won/lost per game
Gui, Add, Text, x66 y380 w100 h20 +Right, ROI
Gui, Add, Text, x66 y400 w100 h20 +Right, Fastest bust
Gui, Add, Text, x66 y420 w100 h20 +Right, Slowest bust
Gui, Add, Edit, x176 y277 w90 h20 vStart,
Gui, Add, Edit, x176 y297 w90 h20 vBust,
Gui, Add, Edit, x176 y317 w90 h20 vBest,
Gui, Add, Edit, x176 y337 w90 h20 vWorst,
Gui, Add, Edit, x176 y357 w90 h20 vWonLost,
Gui, Add, Edit, x176 y377 w90 h20 vROI,
Gui, Add, Edit, x176 y397 w90 h20 vFastest,
Gui, Add, Edit, x176 y417 w90 h20 vSlowest,
; Generated using SmartGUI Creator 4.0
Gui, Show, x705 y84 h463 w521, New GUI Window
Return
ButtonGo:
;SetBatchLines, -1
Gui, Submit, NoHide
Rake := Rake + 0.0 ;a hack to ensure floating point calculations
SetFormat,Float,0.15 ;retain double precision for calculations
GuiControl,,MyProgress,R1-%Reps% ;set range for progress bar
Total := 0.0
Bust := 0
Fastest := Setsize + 1
Slowest := 0
RepNum := 0
Best := BRM * (Entry + Rake)
Worst := Best
mITM := ITM * 10
Loop, %Reps%
{
Bankroll := BRM * (Entry + Rake)
Game := 0
Loop, %SetSize%
{
++Game
Random,rand,1,1000
if (rand > mITM)
Bankroll := Bankroll - Entry - Rake
else
Bankroll := Bankroll + Entry - Rake
if (Bankroll < (Entry + Rake)) ;busto
{
++Bust
if (Game < Fastest)
Fastest := Game
if ((Game > Slowest) AND (Game < SetSize))
Slowest := Game
break ;end this set if busto
}
}
Total := Total + Bankroll
if (BankRoll > Best)
Best := BankRoll
if (BankRoll < Worst)
Worst := Bankroll
++RepNum
GuiControl,,MyProgress,%RepNum%
}
Bankroll := BRM * (Entry + Rake) ;starting bankroll
End := Total/Reps ;average ending bankroll
WonLost := (End-Bankroll)/SetSize ;average won/lost per game
ROI := 100.0*WonLost/(Entry+Rake) ;ROI
BustPercentage := (Bust/Reps)*100.0 ;Rate of Ruin approximation
Delta := End-Bankroll ;average won/lost total
GuiControl,,Start,$%Bankroll%
GuiControl,,Best,$%Best%
GuiControl,,WonLost,$%WonLost%
GuiControl,,Bust,%Bust% out of %Reps%
GuiControl,,Worst,$%Worst%
GuiControl,,End,%End%
GuiControl,,ROI,%ROI%
if (bust > 0)
{
GuiControl,,Fastest,%Fastest%
GuiControl,,Slowest,%Slowest%
}
else
{
GuiControl,,Fastest, Did not bust
GuiControl,,Slowest, Did not bust
}
;SetBatchLines, 1
Return
GuiClose:
ExitApp
The defaults are set to simulate 100 players with 55% ITM playing 1000 of the 1.10 games, starting with a bankroll of 50 buyins. 55% ITM is breakeven for the 1.10s.
If you change it to 20 buying at the 5.20s, you'll see that between 5 and 10 of the 100 players go broke at 55% ITM. Increasing the bankroll to 30 greatly reduces the chance of going broke (as does increasing the ITM, obviously).
Also note that the program assumes that each player continues to play at the given stakes no matter how small or large his bankroll gets. This wouldn't normally happen in real life.