[RuleLawyer]

Yesterday, one of my players hauled out a 'cheat sheet' that showed that Spellcasting had two limits:
1) The Force of the spell
2) and the caster's Mental Limit

Is this right? I don't find the Mental Limit described anywhere.

Second, what's your best source for Cheat Sheets?  What I really need is one where the left side of the page is 4th edition and right right side is 5th edition, and differences are in bold. I play 5th edition weekly and 4th edition monthly and my brain has become mush.

[PiXeL01]

Spells are only limited by force.

The astral limit (best of either social or mental limit) only comes into play in astral space iirc

[Orffen]

What I really need is one where the left side of the page is 4th edition and right right side is 5th edition, and differences are in bold.

I'd love a copy of that if one exists.

[Marcus]

Yesterday, one of my players hauled out a 'cheat sheet' that showed that Spellcasting had two limits:
1) The Force of the spell
2) and the caster's Mental Limit

Ugh those d@mn things are still floating around? Sigh.
That set is quiet heinously wrong.

5th is
Select Spell
Select Target
Choose Spell force setting the limit, (and drain.) (Limit meaning you cannot use more then limit success on the spell)
Cast the spell Relevant skill (Probably) Spell-casting+Magic[Force]
Determine Effect
Resist Drain (Willpower+Attribute (Intuition/Logic/Charisma depending upon character tradition, note: Attribute only Pools have NO Limits)
Determine On Going Effects (IE are you at -2 for sustaining)
Resolve Glitches (Which are so unlikely as to be non-existent in case any competent caster)

4th is basically the same 
Select Spell
Choose force of the Spell (Which effectively does the same thing as in 5th) (while 4th lacks "limit", See Force 182 of 4th 20A it does the same thing)
Choose target
Roll Spell-casting+Magic
Determine Effect
Resist Drain (Willpower+Attribute same as above)
Determine On Going Effects (IE are you at -2 for Sustaining)

They are basically the same.