Removing heat exchanger
 

I am looking to replace all my trannu lines with braided stainless lines, was thinking about bypassing the Heat exchanger , so i would only need 2 lines, I know some guys do this for twins. What are the pros and cons of this?

Besides cooling the ATF the heat exchanger also warms the fluid in extreme cold especially when you cruise long distances with the TC locked when little heat is generated.
That seems like a big con to me considering where you live.

JKM I would have to agree with Bill
That little heat exchanger does a good job and once you remove it you really see how much it does. I have a 12x12 B&M Super cooler with a Spal fan mounted under the box and replaced the front cooler to the big Super cooler and it can still get hot in traffic with a load. The B&M (Long) coolers have a LPD feature where cold fluid bypasses inside the cooler aiding in warmup. Out west with the milder temps we see my trans seldom runs where it should. If I were you I would leave it on and change the lines to it. With my twins it needed to be pulled but relocating it is something I want to do. Just need to find the fittings.