Costa:
Pros: high level of responsiveness, smooth
Cons: harder to maintain, replace keycaps, easy to get stuck with incompatible keycaps
Cherry:
Pros: easy to replace keycap, easier to maintain
Cons: lower level of responsiveness
How to overcome the weaknesses of both Costa and Cherry?
For Costa stabilizers: Step 1: Buy a bunch of backup stabilizers inserts, clips ... from WASD to backup just in case you lose them
http://www.wasdkeyboards.com/Step 2: Lube the stabilizers with High Viscosity lube like Mechlube 1 from Elitekeyboard
http://elitekeyboards.com/products.php?sub=access,misc&pid=mechlubeStep 3: Use Teflon tape to buffer when you have incompatible keycap stems (like SP DSA spacebar) but don't forget to put the inserts as close as possible to the keycap
For Cherry stabilizers: Step 1: Lube the stabilizers with Low Viscosity lube like Mechlube 2 from Elitekeyboard
http://elitekeyboards.com/products.php?sub=access,misc&pid=mechlube_2Step 2: Use Teflon tape to buffer when you have loose keycap stems
Step 3 (optional): Clip the stabilizer