GI Spifire
GJ Spitfire
AVS Spitfire
AHI Spitfire
TGI Spitfire
Tsol Spitfire
DAI Spitfire
Volus Spitfire
Destroyer Spitfire
All those kits are good with the Spitfire. If you want lols use a Spifire on the Destroyer or pick up a pizza while carrying it. You move like a slug.
Some of the kits mentioned here have that "crazy glue to feet feeling while firing" feeling. Doesn't that bother you very much? It does me way more with the Geth Spitfire then the Revenant cause the Spitfire has a pretty long windup until max firing rate, just like the Geth SMG. So having to let go of the fire button to reposition is too costly to dps. Especially when there are still plenty of kits that don't suffer from this (again. Kogans, Batarians, Volus, JetpackTurian, Destroyer, Geth Juggernaut and maybe another class?)
... Course GI don't care about this, since even pre-fully wound up firing rate on him is enough to melt everything instantly. 