Currently I have (1) 38Gh/s Asic Miner cube and was thinking of buying 2 more units at 1/3 of the price I originally paid for my cube ($900).  

3 cubes would give me 114Gh/s total network hashing for about $1500. Is this wise? With difficulty rising so quickly wouldn't a 38Gh/s unit be rendered powerless in the next 3 months?

I don't want to wait for the next gen asic units because I wouldn't receive it until April/May time frame.

Thx Chris