What is your opinion of the TPG services that you have used? By used i am referring to actually sending coins in to them, not just purchasing an already slabbed coin)
I will start:
PCGS
Pros
In auction PCGS slabs tend to bring more
slabs are of a good solid quality, easily stackable.
IMO tends to give a more technical grade
Cons
usually has a very, very slow turnaround
lack of slab options. (ngc multi-coin holder)
can not see edge of coin in slab
Will charge full price for grading even if coin is not slabbed (bodybagged)
Cost of grading (expensive to join the club compared to NGC)
NGC
Pros
Has more slab options (I personally love the multi-coin holder)
"Star" designation can command huge premiums.
IMO toned coins tend to grade higher (this can also be a con)
Toned coins look better in NGC slabs
reasonable grading costs (5 earlybird's when joining club)
Registry
Excellent customer service!
Cons
Turn around time can be long
Tend to bring slightly less at auction then PCGS
Small denomination coins tend to disappear in NGC slabs
Can not see edge of coin in slab.
Will charge full price for grading even if coin is not slabbed (bodybagged)
Imaging service is not worth the $3 per coin, images are lifeless.
I am sure i will think of more. I will be picking up some coins from anacs next week, and will add my opinion of them. I also have some coins out at NCS. I am also considering sending some stuff to SEGS.
Updated NGC 10/27/06 
