I'm planning on getting a natural gas unit heater installed in my
garage, and I had a couple questions.

1) How much difference is there between brands? So far I have one quote
with a Lennox/Armstrong one, and another with a Reznor/Cayenne.

2) The two guys I've spoken with so far both thought that I'd be better
off venting it vertically even though the unit can be horizontally
vented. Both of them mentioned fewer corrosion problems that way. Does
this sound reasonable?

Thanks,

Crhis