Star Wars' mostly numbered races use technology that is about 8-10000 years above Earth technology, while Transformers on themself had 6-8 Millions of years to develop (and use) weapons (not counting the quint and possible pre-quint era)
Right, that was actually a concerted effort, it deserves a response.
Lets go through the supposed technological capabilities of the Transformers depending on which series history we look at.
G1 Cartoon
-The Transformers, even during the Quint Period were suffering from a massive energy shortage (MTMTE), most of the planet appeared uninhabited for all its looks of being in constant work by its denizens as referenced by the episode where Devastator is created by Megatron. The Decepticons were hitting energy convoys even when Optimus Prime was still Orion Pax. Up until the Autobot and Decepticon command forces moving to earth for their little bout the planet cybertron was in a seemingly extreme energy shortage. Now I don't know if you know anything about a highly technological civilization and power consumption, but it would certainly appear that it requires massive amounts of power just to run everything. Even post season 1 and 2 cybertron was getting a relative trickle of energy from off planet sources. Tech levels and advancement were at an all time low, research and development would've been at an all time low and resources would not be nearly as available as they were in cybertrons so called Golden Age (The Key to Vector Sigma)
G1 Comic (Marvel)
-Same Deal as far as tech, but Unicron being a god kinda puts a damper on things
G1 Comic (Dreamwave)
-Again, TFs in major energy shortage, the Great Shutdown (a massive shutdown effort to save the planets diminishing energy reserves) ends too early and the planet needs energy again, but alas there is no where to get it. No energy for walking talking machines means that said walking talking machines don't get jack done.
G2
-Yeah, the Swarm, most energy problems seem past, Liege Maximo, yeah, Jhiaxus (Gee-axe-us) its all very fun. Transformers seem to carry more guns and act more lethal, but energy problems still seem to be abound.
Beast Wars/Machines
-So the Maximals and Predacons carry on the fight now... fun. Their tech hasn't advanced much in the time since their G1 origins, sure they can take on semi-organic forms, but that was being developed long ago. And 'Machines,' don't get me started... suddenly all the stuff becomes Technorganic, so they will not only need energy, but they will need biomass, and heres the best part, being technological for so many years they likely would have no defense against hostile organisms. Hello Imperial Bio and Chem warfare.
Armada.
-Their Best Gun is the Hydra Cannon. They require Minicons to fully fight. They're screwed.
Energon
-Aside from Swarm-spawned soldiers, boring, no true advancements.
And don't me started on the new crap.
Look, the Transformers have been in an overall level of technological stagnation, a Pre-space warfare civilization with few colonies, like two Capital Ships, few transformers with space-faring capability and robots that still have problems with human euphemisms. Oh and they seem in a constant energy shortage!
The military forces of the Empire, Old and New Republics, KotOR era, Galactic Alliance, New Empire, all of them, are scads better equipped for a full scale galactic conflict that the pitiful little armies and lackluster navy of the transformers.
The Star Wars powers are more advanced after around 25k Years of Technological Stagnation (Rakatan Infinite Empire) than the Transformers after a few million.
I could go on, but I think I've made my point.
i want war!!!!!!!!!!!!!!!! 
[ Click to attempt signal recovery... ]
