Hi Mism and welcome to the forum
Perhaps you can tell us a bit more about yourself and your situation to enable us to answer your question.
Financially it's probably cheaper to apply for spouse visa as if you arrive on a fiancé visa you then have to apply for FLR (m) once you're married. Apart from the obvious expense this can also take up to 9 months to process and this restricts you from working in the UK until you receive it.
Plenty of good threads on here to help you decide have a read of this one for starters and come back with any specific questions. Plenty of free advice available

http://filipinaroses.com/showthread....e-Partner-Visa