Looking at two types of pools

My main concern is excersice thus looking for a 8 by 16, 3 to 5 feet deep with a swim unit. My question is this:

1) do I purchase an endless pool with their fast lane built in. I live in ATL and will want to swim year round in an outdoor pool.

2) build a gunite pool with a fast lane or other swim unit.

I am trying to weigh the cost not only to build but to heat and maintain.

Thanks in advance for your help

Jay