It all depends on the coin, grade, value... and what you plan to do (Keep or sell_
Morgan dollars are probably one of the more popular "advanced" sets to collect.
Even being in MS-63, it is still not wise, in my opion, to have some of them grade.
Simply because, let's say the coin is valued at $35 in MS-63. You spend $20+ to get it certified. That leaves you $15.
Versus even selling it raw for $25
But if you plan to hang on to them... I say who cares what they are graded at.
I know many others will differ on this but I am just giving you my

worth.
Now I have sent a couple coins in, but just to get authenticated and attributed. I have yet to send a coin in just to get graded.
I will send a coin in if there is a big price jump. Like the 89-CC
Morgan dollar. Huge price difference between vf-xf, and xf-au.
Any any uncirculated examples of "keys" or "semi-keys" I would probably also get slabbed.