For me it's a question of the 6100 LE is an iconic amp
https://equipboard.com/items/marshall-30th-anniversary-6100
"Used by 7 artists"
It was Jim Marshalls own favorite amp and for good reasons.
"a few snippets from Jim Marshall saying the 6100 was the best amp he's ever made, the 6100 will be the most desired amp ever made"
"the 6100 is the pinnacle of everything Marshall has ever done and probably will never reach again." "All future Marshall's will be only shadows in the path that this great amplifier has made."
"Same thing happened with the Silver Jube. It was an amp to celebrate the anniversary of the company. People don't talk about it much because it didn't last long and not many famous people used them, save for Weezer and a brief stint with Iron Maiden.
The Silver Jube lasted just as long, but has a huge following because of 3 guys: Slash, Bonamassa, and Kravitz."
Let the Axe FX cure you of this marketing influenced thinking. It cured me and it is now my personal duty to let that happen for everyone else.
I found another model worth trying, from a commenter on a different forum with experience with both heads
"A friend of mine had one (6100). Quite comparable to my QuickRod at the time. QR was tighter and a little more aggressive."
Ive gone threw tons of online threads, the bass seems to be pretty muddy on the 6100, which is why I assume you run a pedal in front. The Quickrod by itself with no boost will be less "compressed".