A few advantages that I think L1 has over H1.
L1A - no cap-limit and hence can be applied for anytime
H1B - subject to cap-limit
Period of stay:
L1A - Maximum limit of 7 years
H1B - Maximum limit of 6 years
L1A - spouse on L2 can work after getting EAD
H1B - spouse on H4 cannot work
As far as I know, LCA is not required for L1A petitions.
I think, the L1 petitions are scrutinized more than H1 petitions by USCIS.
L-1A Intracompany Transferee Executive or Manager