I watched it, plus all the special features including listening to the Director's Commentary.
I can't recommend it. I actually fell asleep towards the end the first time I watched it. Didn't really catch the end until I rewatched with the commentary.
At times I was impressed by all the work put into the movie, and could appreciate that on a low budget level. There were things they could have gone even cheaper on, but at least I could tell that people put some real work in. Like scenes with over 10 extras in a gunfight. Pales in comparison to even mediocre spaghettis that had scores of extras as soldiers fighting scores of extras as bandits of course. Ultimately, a lot of the movie was simply unsatisfying. Would it have looked better with a similar reverse inflation adjusted budget in the 1960s if done by Italians in Spain? I have to wonder.
A lot of bizarre things happen, as mentioned in this thread already. Guy has a gun on Trejo, and then watches Trejo put a gun together, and stands motionless as Trejo shoots him. Then he flys through the air on a wire pull. One other strange bit was riding a horse up a flight of stairs to chase a bad guy, then getting off the horse, and bad guy runs away or whatever. Basically there was no point to the horse up the stairs gag. It didn't matter, it was so throwaway by the action that followed that it had no reason to exist. Ride horse up stairs, get off horse, do nothing. It's not like Trejo rode the horse up and then leaped off his horse to tackle a bad guy, or had some crazy horse duel on the second story with the horse leaping down. No, he just rode it up, got off, then went down the stairs or whatever on foot. Big waste of rebuilding a staircase to support the weight of the horse when there was no payoff.
The central conceit of the plot was just kind of, "huh?" So Trejo dies, goes to Hell, and makes a deal with the devil to go kill the other guys so that Satan can have their souls. But all those guys are going to hell eventually anyway once they die, so why would Satan give a damn about having to wait a few human years?
The movie looks ... bad at times. It was shot on RED cameras, but sure doesn't look good. There are some shots that maybe slipped through the grading process or something, because some shots look just like they were pulled from a 1980s vhs camcorder. Real awful video look. Other times ... eh. The director went with a harsh sidelight on everything, and badmouthed traditional lighting setups in his commentary, so that explains why it's all so dark.
Other things gleaned from the commentary:
Filmed in Bucharest, Romania. The studio they were at had a western town backlot built for Cold Mountain. It was in disrepair when scouted, but luckily for Dead in Tombstone, it was renovated for that Kevin Costner Hatfields and McCoys tv show before DiT started filming. Plus the 'Hell' set and the goldmine set were leftovers built for Ghost Rider 2 and redressed. Basically other than redressing and a couple of fronts built for the purpose of blowing up buildings, everything was cheaply appropriated from previous movies. A movie Fidani could love.
Universal wanted an original vehicle for Trejo, asked Reine for pitches (he directed Trejo in Death Race 2 and Death Race 3). Reine pitched two westerns, Universal bought this one, and insisted the name be changed to include 'Tombstone' in the title. Who knew that Trejo was a such a star that Universal would tailor make projects for him?
The budget was 3.5 million to start, but when Mickey Rourke was added, the budget ended up at 4.5 million. Which seems to me that Reine was saying Rourke was paid a million for however briefly he showed up, but who knows, maybe they added other stuff after Rourke that brought the price up.
Only a few of the guns on set could even fire blanks, so that is why a lot of the gunfire is that awful CGI gunflash stuff. So tons of pistols and rifles are just CGI nonsense. Plus the gatling gun sequence, all CGI smoke and fire. Disappointing.
Reine only mentioned Once Upon a Time in the West as far as spagehttis go in his commentary. It sounded like he was much more influenced by American westerns, and spoke of seeing german-dubbed American westerns on television as a child.
Reine did mention towards the end of the commentary a hope for an entire series staring Trejo's Guerrero character. So maybe another one will get made.