Hi iamsupernikki, welcome to the forum
For your question.......Well it's your personal choice really.
A Fiance Visa, is granted for 6 months validity during which time you must get married(the Fiance is not allowed to work). Once married you apply for FLR (Further Leave to Remain). This will be for 27 months and allows your spouse to work.
After 2 years the spouse can apply for ILR (Indefinite Leave to Remain)
There is a cost for all three Visa's
A Spouse visa is granted for 27 months (FLR) and allows the spouse to work right away. After 2 years the spouse can apply for ILR
So solely on financial grounds for visa's the spouse visa offers a saving.
In terms of the applications and requirements they are very much the same
Getting married in UK or Phils also has a different cost base. But again your personal choice.
Wishing you the best of luck whichever way you decide to go.