I was in this exact situation back in 2017 where the company offered to do L-1B with blanket approval that would have had me working within weeks, but I opted to stick with K-1 to AOS faster without any dependency on the company in case my new role didn't work out. However, at the time EAD approval times were 3-4 months so I just took a long-ish vacation and the company was fine with that.
With the current wait times I'd probably have gone with the L-1B, I'm not sure my company would have waited a year for me to get EAD. If it had been L-1A on the table it would have a no-brainer since you can transition to EB-1C without PERM certification and have a green card in hand in less than a year anyway.