I know, I'm being a grammar ****, but it's NOT an investment.
Investments are things like stocks, bonds, etc. that make you money.
Your camera is an expense. Even if you use it for business as a
photographer, it's still an expense. The only way it'd be an
intelligent investment was if it didn't consistently depreciate in
value over time, which all camera bodies do.
Technically, things like education are not investments even though
it's frequently called "investing in yourself/your future/etc".
That's also an expense, albeit a worthwhile one.
Sorry, I realize that does very little to answer your question, I
just needed to get that out. My inner Linguistic Commando is now
sated.
You're in a great position right now as the cheaper Rebel bodies
are very close in performance to the more expensive models. As
long as you treat the plastic body carefully, there shouldn't be a
reason it wouldn't last as long as one of the magnesium ones. If
you like the feel of the 350 in your hand, I'd say go for it.
Another option is to buy a used 10D, which are going for dirt cheap
these days.
Glass is a great thing to spend money on. It holds its value very
well, and the 17-40 will work on all EF and EF-S mount cameras.
It's not my personal favorite, (the 24-70 is what I'd use for my
kind of shooting) but it's a great lens. I'd always recommend
buying the best glass you can afford, then worrying about the body
after that. Those have an upgrade cycle of every 5 years. Lenses
can last you 30+ if you treat them well.
Good luck,
jb
--
--Laws alone can not secure freedom of expression; in order that
every man present his views without penalty there must be spirit of
tolerance in the entire population.
--Albert Einstein