I got one of those a few weeks ago specifically to cut the bottoms off of aluminum CO2 & steel gas bottles. The thoat is small and the bottles had to be turned often, but the cuts came out straight - even after all the turning.
Already broke the blade that came with it; +2 on getting a good blade and a couple of spares.
Lincoln Power MIG 140C Victor A/O
Dewalt 14" Chop Saw IR 20gal 5hp Compressor
Craftsman bench grinder, tabletop drill press
Carton of Common Sense: Medium
Box of Experience: Small
List of things to learn: Long!
Oh,, an old 360 Green Card and a 370 Yellow Green Card too..