I have been dealing with TOS on both sides for about 9 months now and I am scheduled to have my first rib resection next week. I have been doing PT for about 2 months now and I am starting to see some improvements within the last two weeks but I also haven't been working and hardly doing anything with my hands for the past month. At this point I am debating on whether I should go through with the surgery or go back to work and hope it doesn't get worse again.
Another concern of mine is if I don't get the surgery now what are the odds of me needing it later down the road in 5 or 10 years and at that point would I be better off doing it now as more of a prevention.

This is not a surgery you get for "prevention" purposes and I am very much of the mind usually "rather do it now than later." I had two shoulder surgeries previously. The first one was for my left shoulder that was absolutely trashed. A year later I did the right because it was gonna be in the same condition eventually, but had that been my only shoulder affected, I wouldn't have been at a surgery level yet.
In regards to a first rib resection, so much can go wrong leaving you worse off that I would not recommend it as a preventitive especially if you're getting better with PT. If you're debating surgery, it's not the right time to get it. 9 months is not a long time to have TOS and to be working on it.
You never know what will happen in the future. Perhaps you'll need the surgery later. But if you can avoid it at all, I recommend doing that. Nerve damage, clotting, permanent debilitation, collapsed lungs... all complications of surgery and the rate of success is not very high in regards to other surgeries. You're looking at a 70% success rate where success is measured by "not worse than it was." The percentage of people who actually feel better after surgery especially with NTOS is lower.
Now, you didn't mention what kind of TOS you have. If you have something like arterial TOS and your doctor is recommending surgery, that may be a different story. That is only 2% of people with ATOS, however. That can be dangerous to not have surgery for.
2 months of PT is a short period of PT. From what I understand, surgeons usually don't want to even think of surgery until you've been in PT for at least 3 months. Did you have prior PT? If not, I really recommend postponing surgery if you're seeing results in what is considered a normal time period for TOS...

I truly hope you have an expert surgeon doing your surgery, this is not a time for someone to practice on you.

And don't be afraid to cancel if you have any doubts.

Can you give us more info on your diagnosis (ATOS,VTOS,NTOS, disputed etc) symptoms & avg daily pain levels?
We can help better if we know more details.

Really good & long term results from expert PT may take a year or more , 2 months is just a start , give PT a bit longer unless you are in severe pain.

Took me about 2.5 yrs but had some wc delays in care & therapy.. a really good chiro/therapist fixed me up. Plus lots of self/home care.

Our important sticky threads- Drs/PTs, useful, trigger point info -
http://neurotalk.psychcentral.com/thread135.html
http://neurotalk.psychcentral.com/thread84.html
http://neurotalk.psychcentral.com/thread125577.html