AiM9Ls
Sorry to come to this topic late. However, apart from the head-on aspect, a major advantage of the L over the G and earlier variants was its ability to counter the flare threat.
Wiggy, I think your memory is playing you tricks about the Wtm Wg getting 9Ls before the conflict. If my memory serves me right, our boffins developed the SWIFT mod for the 9G at extremely short notice in the lead-up to the conflict just in caser we couldn't get our hands on any Ls. Also, after the conflict we had to persevere with 9G(SWIFT)s for some time before getting Ls as the 9L procurement was earmarked for the SHAR.