I have seen instances that appeared to me to be speedhacks - but only occasionally. This prompted me to do a little research on the subject and I found that there are a handful of forums out there dedicated to providing information and programs to cheat in swtor. Anyone who says that cheats don't exist and its just bad players complaining have obviously never looked for hacks because they ARE out there and they are not hard to find. I just hope the bioware devs are spending the 15 minutes it takes using google to track down these hacks and find a way to block or detect them.
edit: The hacks that these sites claim to offer in working condition, although I've never tested them, include speedhacks, resolve immunity, and free rage/focus/heat/ammo/etc. For obvious reasons I'm not including links but again, it takes very little time to verify that these cheats are out there.
Why anyone would feel they have to cheat in this game is beyond me. I've played since day one of early access and I have seen a few things, hiding in the place the ball spawns in huttball and not being targetable is the most common one I have seen but it's the same player doing it on my server and they are so bad it's hilarious.
I've play in a rated team that gets accused of hacking though, I think it is very rare that people hack and most occasions it's just players making excuses for losing to better skilled and geared opponents, or they don't understand class buffs/mechanics.