on PBE 6.3:
It does not really solve the problem because the 
is much better.
If you want the support include these boots it is necessary increased the basic mouvement speed to 45.
Ya thats a really good point. Thats why i dont buy mobis except on maybe assassin junglers. If the base movespeed was 45 like everything else they would be useful.
its not that swifites are particularly great.
the only reason swifties are so good now is that the game is loaded with slows, and merc treads arent as good as they used to be against cc. 20 tenacity and next to slows there is so much knockback and knockup that tenacity doesnt mitigate.
couple that with the amount of damage in the game right now, and it doesnt make much of a difference if youre stunned for 1 second or for .8 seconds when you still die during the stun.
if anything, then just give mobies a similar passive as dead mans. meaning the movement boost decays when cced or taking damage instead of completely falling off. but dont make them give more speed.
Swifties will always be more useful since while they give less MS than Mobis activated, they give more than normal boots and give slow resist.
Mobi are hit or miss since as soon as you take any damage you aren't escaping anything so its only good for all in champs. Swifties are good for any champ in the game. Hell sometimes I even take Swifties on Morgana over Sorc or Lucidity just to move faster.
45 basic mouvement speed and 95 after 5 seconds would be more balanced
