Slitherine

1 small AD inf (40) + 1 large AC inf (42) + 1 small AC inf (28) = 110

2 large AD inf (60)(60) = 120

For 10 pts, it would seem the second option is the better one: better shooting, less hits on both front units, better CTs in all situations.

Any benefits to going with option one besides the saving of 10 points?

Benefits of the extra unit option:

1. The small AC unit in a 2nd line can stop cavalry passing through
2. 7 ACV against 6
3. Every extra unit you have in your army gives you a better chance of deploying units last.
4. The rear unit can swing from rear support to a flank to provide flank protection if neccessary, or can be left behind to guard your LOC.
5. The rear unit can provide rear support in close combat - meaning you may feel a little more comfortable facing cavalry if you want to stand and fire rather than form square.

In summary, the 2 x large AD option gives you a stronger front line, and allows much better brigade double moves. The 3 unit option is weaker frontally, but may provide some deployment and tactical advantages.
You pays your money and takes your choice!

Cheers
Brett