Gas here, tbh the advantages do seem to outweigh the initial outlay and running cost. I've done a limited number of jobs (read less then 10 or so), but the time saved even on maintenance cleans should more then make up for the slight increase in running cost. Finally got my lovely alu. mushroom vent in, just waiting for the rain to stop.
Warm hands, easy to use hose, reeling back in as well. Dirt just flies off the window. Easy to set up, easy to fill.
Disadvantages would be insurance, can't think of another one.
ps. there is no chance of a gas explosion. Lpg tanks are made to vent before pressurizing so much that it will blow. Unless the safety system is bypassed or sabotaged. Sure you do get a nice cooking flame, but I think you'd get the point after your van is on fire. Also, I don't have any leaks at all. Which I am glad of. Some brushes aren't suited for hot, but others shouldn't have any problems. Gardiners flocked dual trim seems to be holding up nicely.
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