Get the drysuit.  You can pick up a nice new suit for under $1000 as long as
you stay away from the LDS.  Bare makes some halfway decent suits and you
can usually find even their top of the line suits for under $1000.

Then tell your buddies how great it is and get them to buy drysuits too....
unless they already do, then you need to get one ASAP ;)

Jon

The nature of the wetsuit with a nylon inner lining prevents it from being
called semi-dry in all but marketing campaigns.

The warmest wet suit, all other things being equal is one with NO inner
lining. It was abandoned with great joy when the S2S (skin two sides) suit
came on the market.

The best wetsuit on the markete today is th Henderson Goldcore which has
solved the problem of trying to put a wet suit on with out depleting the
world of talcom powder.

The best wet suit in the world is far inferior to the worst dry suit,
especially at depth.

As others have told you, a dry suit is the way to go, but if you're not
doing long bottom times in cold water and really don't want to spend the
bucks, the semi dry is an option. I have many dives in 48-50 degree
water in a Mares Isotherm and also in an old Rofosub semi dry. The Mares
is an extremely warm and comfortable suit, and I had no problem at all
doing 50-60 minutes at that temperature in it. It's hard to compare it
to the Rofosub, because the Mares was new and the Rofosub was 15 years
old. I liked the neoprene seals on the Mares; it was very comfortable on
the neck. I liked the integral hood and the neoprene seals on the
Rofosub. Be careful of the fit on the Mares though - they don't do
custom, and if it doesn't fit, it doesn't work. It is still a wetsuit;
the seals only decrease the exchange with the outside.

Another option is a custom wetsuit with latex or neoprene seals from one
of the places in CA or FL . Also look at Atlan; they make nice semi dry
and drysuits at a reasonable price. An Atlan or other neoprene drysuit
is another medium cost option.

If you really like to dive and don't want to move to where there is warm
water, the shell drysuit is your best bet. It is really nice when the
air temp is in the 40's or 50's. You get out of the suit, and you still
have on a nice warm dry undersuit.

al

I bought the Mares  and love it.  The only problem is that the zipper is
on the back of your shoulders, and requires someone to zip/unzip.  I
haven't figures out how to do it myself yet, but I've waxed it a lot.
You get just a little water in it.  I get over to Delaware for one week
a year, and had a hard time justifying the cost of a dry suit.  My other
 diving in Morehead City, Florida, or the Caribbean.  I bought the
Mares from LeisurePro, so I got something off list price.  My favorite
LDS, doesn't carry Mares, but they won't see me diving from  their store
in Alexandria anyway.

Try once a 7mm semi-dry from Waterproof. I have one and am very happy with
it. It has a top-quality drysuit zipper and good seals, so if you want you
can stay almost completely dry. When it gets to hot simply pull the neck
seal open to let some water in. In fall, before I switch over to my
drysuit, I dive with a t-shirt under it. I know a guy who also uses it
during wintertime and he doesn't seem to have cold to me.