[proberts]

I was assuming that you qualified equally for both visas but from an outcome standpoint, if the employing U.S. company doesn't qualify as a "blanket L" company, then it can be very tough to get an L-1B visa (which is for professionals/non-managers) because the process goes through USCIS. So, from an outcome standpoint, unless the employing U.S. entity qualifies as a blanket L company, it's much easier to get an H-1B visa.

[brit_in_america]

I was rejected initially without a blanket petition and then approved after the blanket petition was in place.

My experience matches exactly what you have said.

One benefit I forgot to mention of L1 is that spouses can work incidental of status. L2S is essentially an open work permit but is tied to the validity of the L1 visa.