nope , doesn't differ much , i used to use both for a long time , then i used a 16 gb sdcard with data2sd (2gb ext4 partition ) , i don't know what class was that but i knew it was good , so i tell you try wiping all data , dalvil cache ... then try reflashing your ROM ( i recommend you use eqdkp ) , then use link2sd to mount your second partition , then refollow my instructions .... please press the thanks button and check the SENSE 4.0 lockscreen and clock !
Phone : Google Nexus Prime ( Galaxy Nexus )
Android Version : Jelly Bean 4.2.2
ROM : Unofficial Rootbox nightlies
Kernel 3.0.xx , fancy kernel !
Overclocked up to 1.4 , currently 1.2 GHz (Using Quad Core Manager Plus for battery saving)