It depends on what's most important to you. One type might use less room, so
if real estate is limited one will be more favorable. If you want DC isolation the
Coupled line is good...
One point of view is:
Look at what your design tool has as examples. They typically give examples that
correlate well with their simulations .
I can share you some information on the substrate.
Of course PTFE is the best if you can suffer the cost. RO4003 can also be used with a compromised insertion loss and price. I know FR4 and any lower spec materials could also be used, but it takes a lot of time to characterize the material.
helo..can someone teach me how to design parallel couple bandpass filter with specification, center freq=2.437GHz,upper freq=2.448GHz and lower freq=2.426GHz..??what are the steps that i must follow??