My vote would go towards getting an Avalon batch #3 order in. It seems appropriate to grow with the network using the best and most cost effective tech available at any given time.
I don't recommend this given the outrageously high price and the unpredictability of profitability depending on BFL / ASICMINER's deployment.
Is profitability really unpredictable? What is the upper bound of network hashing power and the latest date to break even?