Recovery missions are riskier than an airstrike. While they do provide roughly twice the profit ofincome, they also carry a risk of taking casualties. Also from experience: the difference in profitincome just about covers the price of hiring new soldiers to replace dead ones. On the other hand, surviving soldiers receive experience and attribute increases. In the end, it is up to you to decide whether that risk is worth taking, and that depends on your playstyle, difficulty and game mode.
In normal mode, it boils down to your patience and/or willingness to save scum your way to victory. In ironman, you need to adjust the recoveries you attempt according to your losses. Unless there's new technology to be acquired from the mission, it's relatively safe to bomb the site.