As others have said, it’s hard to beat a stock 800 with the right pedal.
I’ve had JVMs (twice), a Splawn Nitro, currently have a Deliverance 60 (may be up for sale soon) and hopefully soon an Engl Blackmore.
The Nitro had an amazing low end, but it gets kind of old after a while and then amp ends of feeling like a one trick pony IMO. I was happier with a 6505 TBH.
I had a love/hate relationship with the JVM 410 and because of it almost swore off Marshalls.
Now I have a Mojotone 800 and couldn’t be happier with that amp. The Deliverance is a great amp too (just check out Blake’s clips), but I seem to be always more at home with the 800. As far as simple amps go, I think it is very versatile because the gain character really changes with the type of boost you use.
Trust your stuff.