Trying to decide on a new amp

the slo 100 is the finest of high gain amps in my book though its in the marshall camp; bright, edgey and low on actual bass, but it cuts a mix and sounds like gold, best preamp distortion and a well defined chunk from the exceptional transformers. Mike got there 1st and did it best. The clean tone is the best of any channel switcher I've personally played and the 'overdrive' setting is pretty much an 800 preamp. I am not a PCB fan in tube gear but this is the best constructed current production PCB based amp, the baord is truly milspec and anything that could pull free and wreck a gig is wired off board via flying leads like an 80s marshall, as god intened. I would take this over the bassman/plexi type model T any day. Or get an actual pelxi or Laney supergroup/klipp. I played superleads for years, they are mean as hell when used in anger... neither of these amps will produce a 'brown note' that's more of a moog synthesizer through a 1000+watt PA with subs thing anyway

avoid the rectifier and peavey unless you like repair bills or want to learn to replace power tube sockets or fets in switching circuit all the time.... I can't speak for the thunderverb directly but the construction of most modern oranges does not inspire confidence.

the meatsmoke is in the sunn camp.... I've never been impressed with bogner but I've heard them sound good.... I've never had anyone ask me to repair one.

Did we do this already or was that someone else?

conventional speaker can't produce 5hz so you're eating amplifier headroom for nothing, that will require a subwoofer with its own amp and no one will know its happening anyway

read the handbook of acoustics

iommi was dark and doomy, he invented it.... he used off the shelf laney supergroups and a modded treble booster. I think anything on your list will do doomy, heck, a pinned fender into a 4x12 can get there. but the ridiculous requirements viz a viz sub-bass reproduction in bizzare drop tunings that are lower than low were getting quite comical and I had to say something

just get a slo100, its good enough for matt pike these days

the slo and deizel have a lot in common in gain levels and the way the distortion is produced, the deizel is defintiely a descendant of the slo100 via the dual rec and 5150 etc. All these amps are basically tweaked soldanos with ineferior components and more features. If you don't need the 4 channels get the soldano. There's less that can go wrong with their switching due to it only switching between 2 channels and also the leegance of the design and quality of components chosen...

and I'm telling you the slo100 has the best transformer set in a current production amp and the build quality is second to none. The deizel ahs more features and versatiliy, the slo is a better product though. The SLO has giant iron in there and has more capability to pass extreme low to your speakers. A big, high quality OT is key for this, the amp can always be modded for more bass.... there are a few coupling caps hereand there that could be increased a bit without flubbing out, there's a rbight cap that you may not need on the input.... and some of them have depth controls and turning that up and the keeping the presence low will let a lot of low pass the power amp by lowering the local negative feedback in lower frequencies although you will also be sacrificing punch and clarity at those frequencies.... for djent maybe not good, for drone it will be fine

I really don't think there's a finer high gain head than the slo100. The inside of this amp is a night and day difference from a mesa for instance which looks like an overcrowded mess with lots of ribbon connectors etc that are better suited to a desktop PC than an amplifier that will be gigged and toured. THe only other option is the meatsmoke, whichas far as I know is a hot rodded sunn.... sort of a 2000S with a high gain channel. it will deafen you and everyone you know. Another option is a hiwatt 200 which is probably the loudest 4 pwoer tube amp I've ever heard, they're indestructible but you'll need to add gaina s they don't break up at all and the master has nothing to do with producing distotion.... 200 watt vintage oranges are pretty decent but mainly have inferior parmeko transformers.... anyway

slo100

this is what an amp with PCB should look like inside:

https://www.musiker-board.de/attachments/soldano-jpg.739504/

here's some other examples of soldano-like circuits on your list

VH4: https://www.google.com/imgres?imgurl=http%3A%2F%2Fspinoo.free.fr%2FprojetG5%2FImages%2520Amplis%2FDiezel%2FVH4%2Fvh4_pcb5.jpg&imgrefurl=https%3A%2F%2Fwww.mylespaul.com%2Fthreads%2Ftubes-attached-to-circuit-board-vs-tubes-not-attached-to-circuit-board.122368%2Fpage-2&tbnid=xrIV-vUQ7NDLiM&vet=12ahUKEwij-ffhgMfvAhUHMN8KHbd9C5wQMygIegQIARB5..i&docid=lDjm7Rda4pGGHM&w=1024&h=768&q=diezel%20vh4%20guts&ved=2ahUKEwij-ffhgMfvAhUHMN8KHbd9C5wQMygIegQIARB5

mesa rectifier: https://captainbob.de/publicuse/mesa_dualrectifier.jpg

see a difference yet?

big differences, the soldano has everything off board, all the tubes, as they should be because PCBs hate heat and tubes get hot, the leads are all well dressed on the soldano with good quality wire run neatly... the other 2 have on board tube sockets and multi-lead ribbon connectors in places.... the soldano ahs lots of space whereas the mesa and diezel are very crowded in places.... the layout of the diezel is really weird ebcause there was space in the chassis to avoid the build they settled on, its very odd.... the emsa is multiple PCB even the knobs, its a emss.... I've worked on them, they are a nightmare when they go down and they ALWAYS go down

if you know what you're looking at you can see the soldano is worth every penny in buld quality and the other 2 examples are mainly trading for big money based on the feature set.... you seldom get both.... between the mesa and the VH4 I would take the VH4 but really it looks like a nightmare of eventual service problems to me... I'm sure its a fine amp if you can afford a backup.