Damn guys, I wouldn't do 4 BTC either. What calculations are you running that suggests you'd see that back?
If you think Bitcoin will ever go over $110 then the calculations are different.
The price of BTC has no relevance, because you have to compare to the opportunity cost of buying and holding BTC. If you spend 4 BTC today, and over the next 6 months make 2 BTC, even if the price goes up to $1000 per coin, you are still losing money...