I did it in Ashbourne a couple of years ago and transferred to Drogheda when it was on Termonfeckon Road. It was much the same price as a gym, it didnt work for me, didnt lose anything and i was going 3-4 times per week. A few friends have done it and it worked for them.
To be honest, put your runners on, ipod in ears and head for a walk, its what works for me and soo much cheaper. Think of the time to drive to and from curves and your 20-30 mins there, you could have 4-5 km walked in that.
L