I'll second everything that Shane said -- saltwater is amazing
It's well worth the bit of extra effort I think -- and once you've got everything up and running (depending on what you keep of course -- I stuck with the easier stuff), the maintenance really isn't too bad either.
Your initial investment is going to be big though -- be prepared for that. The tank/stand is just the beginning. A good skimmer will run you a couple hundred. If you decide to go with either a FOWLR, or a reef tank, live rock you pay for by the lb, and you should have about 1-2 lbs/gallon... expect to pay sevreal hundred on rocks. Livestock itself is expensive as well... you might be able to find a couple of fish in the $10-15 range, but most of them will run you $25-150... Ditto with corals -- $35-150, depending on the size of the coral, and the the type. Sand can get expensive too -- I've got a 4.5" deep sand bed in my 90 gallon reef (it helps with biological filtration), and that worked out to 200 lbs worth of sand. Each bag is about 30 lbs, and will cost $30-40 ...
That being said, I'm moving at the end of the month (across the country), and I'm not taking my big tank with me -- I've sold all of the fish and the rock that I'm not taking -- but if you were interested in some sand (and live anywhere near Toronto, I don't know if you do), I can definitely sell it to you cheaper than the pet store -- the bonus being that this stuff has been in my tank for 3 years, it's full of useful bacteria/critters etc. It would be called "live sand", and places sell that for at least $3/lb.... I'm taking a bit with me (I do plan on setting up a tank when I get out to Victoria, it just won't be nearly as big so I have no need of so much sand), but I should have around 150-175 lbs of it left -- I could sell it to ya for less than the cost of 2 bags of sand -- which would probably barely cover the bottom of your tank
Anyways -- whether you want the sand or not, I think that you should give saltwater a try
It's just incredible, as long as you don't mind putting the money into it to get off on the right foot. One of my favourite books to read on the topic is The Conscientious Marine Aquarist ... great book, lots of pictures, and it gives a good description of the different fish species etc. I think that the author is Ron something -- I just packed mine up, or I'd check for you
I haven't updated it in a while, but you can also check out my website that I set up when I was first starting up my tank...
http://www.geocities.com/marinehaven
HTH
Jen