Power Cord is a relatively soft polyester tennis string. This is not to say that it feels like a multi-filament string, its still a polyester and as such has an inherently firm feel.
If you have come to enjoy the performance benefits of polyester strings but have wished for a livelier more forgiving (softer) feel, then Power Cord is a tennis string you should try.
If you have found that a 'full' (non-hybrid ?) polyester setup is too harsh on your arm, Power Cord may be the answer. Its higher elasticity produces a livelier and softer string-bed that is easier on your arm. As far as spin generation is concerned, nothing beats a 'full' polyester setup and a 'full' Power Cord setup is no exception.
For tension ?, start off with whatever tension has worked well for you with other polyester tennis strings.
First off, if hitting harder with more spin appeals to you, then you should at least try a polyester tennis string. Thanks to its softer more elastic feel, Power Cord is an ideal polyester to start off with. Transitioning from a non-polyester to a polyester string will almost invariably result in a string bed that is stiffer than you are used to. Employing a softer polyester like Power Cord will achieve a string-bed stiffness that is closer to what you are already familiar with.
In the spirit of making the transition as gradual as possible, start off with a hybrid ? will provide a feel that is setup. Pairing Power Cord (usually in the mains) with a string like Golden Set Synthetic Gut (usually in the crosses) will achieve a string bed stiffness that is closer to what you are already comfortable with. If this works well and you are open to a further increase in stiffness, THEN try a 'full' (non-hybrid) setup with Power Cord on its own. You will find that a hybrid Power Cord setup provides impressive spin generation. Even more impressive is the spin generation of a 'full' Power Cord setup
For tension ?, you should start off stringing a polyester at about 10% less tension than your preferred tension for non-polyester string.
Power Cord, with its increased elasticity, might just change your opinion of polyesters. While it shares the incredible spin generation inherent to the polyester family of tennis strings, you will find it to be noticeably softer and more lively. Going back to a non-polyester setup may be difficult after trying Power Cord.
Since your avoidance of polyesters stems from their higher stiffness, you should NOT be using Power Cord on its own in a 'full' (non-hybrid ?) setup
Nor should you be stringing it at the tension you prefer for non-polyesters. A noticeably softer feel will be achieved by stringing Power Cord in a hybrid (combined with a softer string like Golden Set Velvet or Synthetic Gut) and at 10% less tension ? than you prefer for non-polyesters.
Take whatever tension ? you have been using for a non-polyester and lower it by 10%. If that is still a bit too stiff, further reduce the tension for your next restring. It is often surprising how far you can lower a polyester's tension before loss of control becomes an issue.
Start off with whatever tension ? has worked for you with other polyesters.
Going with 17, the thinner gauge ?, will provide you with increased feel and spin. For you, durability is not a big enough concern to warrant using the thicker 16 gauge.
Going with 16 gauge ? will maximize durability while going with 17 gauge will provide an enhanced feel along with increased spin. It is a difficult decision for a lot of players because you inevitably are forced to sacrifice either durability or performance. Something of a compromise is obtainable by installing 16 gauge in the mains and 17 gauge in the crosses. Such a hybrid ? combination will yield durability on par with 16 gauge as well as improved performance.