Power commander is only needed if the bike's hardware state required a tune and there are no custom tunes available. So it depends on what you do. If you remove the cat and the bike is a 1700 (as i see u have) then there are 3 tunes i know of you could download for it. One is for the 1700 with tors and cat intact and is made to use instead of the stock 1700/tors tune not because it isn't fine, but it is supposed to perform better. Another is for decat (cat removed) with tors. And the 3rd is the same as the 2nd except it's got a bit more fuel added in the performance ranges for use with the same setup except with the seat hack done. That tune is one i altered from the 2nd tune after i removed the air duct piece from under the seat. That with the extra fuel give a really nice boost over the decat tune. Those tunes were made on a dyno by one of the few people that will use tuneecu to dyno your bike. Thats a free app that is another tuning solution along with power commander and tuneboy. So with that free app and a laptop you can load any of those tunes into your bike.
Now, if you have a hardware setup different than what any of those tunes are for, then you have to get your bike tunes. The power commander is one way. Cost ya bout $800 for the device itself, installation and a dyno tuning. Tuneboy is about the same $ except it is NOT a hardware device like the power commander, but a software one like tuneecu. But like i said, there are hardly any tuners who will dyno your bike with tuneecu, so thats not an option unless you live near someone who does, and there are only a handul in the world who will dyno your bike with tuneecu. Those maps i mentioned were made by a tuner up in northern california for a forum member at another forum and he posted them for others.
So in short, if yours has tors or other aftermarket pipes, a free flow filter, and the cat removed, you can use the 2nd or 3rd map. If you have pipes and filter but the cat is intact, i would stick with the triumph tors tune because the custom map i mention for the bike with cat intact does not IMO improve anything much if at all and gets worse gas mileage. the other 2 get worse mileage too, but you get your moneys worth in better power.
if you have any of those setups