ikeonet1

I agree with Numistacker.. I've focused primarly on 1/4 and 1/10 mainly due to affordability. During the recent spike, I've traded a few of my gold pieces back to silver or larger pieces of gold. I try to stick with gold that I can get where the premiums are flexible. I recently did a trade of a $10 indian 1/2 AU Details, $2.5 indian, and 1/10 Lunar horse + a little cash for a  2015 1 oz libertad, although with rim dings. 
In another case I sold off a 2006 1/4 panda (damaged) and a 2012 1/10 panda and picked up 6 x 10 oz JM bars. I leverage the premiums and demand to do a conversion. My total input $925 for a conversion to 60oz of premium bullion ~$15.42/oz.
This is not the case for a lot of 1/4's, definitely not for eagles, philharmonics, etc. The bullion value is just the price floor. The premium is the demand that can be leveraged in a trade deal or sale. In the case for the indians, I would've never got the full cash value because they were AU details, but now I have a full 1 oz which can be realized for full bullion value at anytime, same with the JM bars or use the premium to do it again.
The 1/10-1/4 has some of the biggest premium gains out of the fractionals. The more in demand the better, like the 1/4 QB which also did well for me. I try to buy at spot, very close too it, or trade under it (with existing inventory). If you do pandas, DO NOT remove them from OMP. They lose 10-20% unless they are graded and slabbed. I sold off my 2006 because it had a little mark and left $150 on the table. The premiums are all in the condition or grade for the collectors.
One other note with the semi-numi, if spot went down I would've been able to convert at much better ratios, but considering spot went up I got less. 
Btw, i don't know the performance of the 1/10th brits that could be a locality thing. Pandas though are world wide. I also like the somali elephant but the premium is too high for me right now.

I agree with Numistacker.. I've focused primarly on 1/4 and 1/10 mainly due to affordability. During the recent spike, I've traded a few of my gold pieces back to silver or larger pieces of gold. I try to stick with gold that I can get where the premiums are flexible. I recently did a trade of a $10 indian 1/2 AU Details, $2.5 indian, and 1/10 Lunar horse + a little cash for a  2015 1 oz libertad, although with rim dings. 
In another case I sold off a 2006 1/4 panda (damaged) and a 2012 1/10 panda and picked up 6 x 10 oz JM bars. I leverage the premiums and demand to do a conversion. My total input $925 for a conversion to 60oz of premium bullion ~$15.42/oz.
This is not the case for a lot of 1/4's, definitely not for eagles, philharmonics, etc. The bullion value is just the price floor. The premium is the demand that can be leveraged in a trade deal or sale. In the case for the indians, I would've never got the full cash value because they were AU details, but now I have a full 1 oz which can be realized for full bullion value at anytime, same with the JM bars or use the premium to do it again.
The 1/10-1/4 has some of the biggest premium gains out of the fractionals. The more in demand the better, like the 1/4 QB which also did well for me. I try to buy at spot, very close too it, or trade under it (with existing inventory). If you do pandas, DO NOT remove them from OMP. They lose 10-20% unless they are graded and slabbed. I sold off my 2006 because it had a little mark and left $150 on the table. The premiums are all in the condition or grade for the collectors.
One other note with the semi-numi, if spot went down I would've been able to convert at much better ratios, but considering spot went up I got less. 
Btw, i don't know the performance of the 1/10th brits that could be a locality thing. Pandas though are world wide. I also like the somali elephant but the premium is too high for me right now.

1/10th definitely worth picking up if you ever see them at close to spot.
On new issues, expect to pay around 15%.  I buy one of each as I collect them but I wouldn't stack them at that price.  The Panda and Somali Elephant however would be worth buying and holding as investments.  The premium on those should go up over the years.

The coins which change designs are a better longer term hold than the brits and phils.
@ikeonet1 did a good video on fractional gold a month or so ago if you can search it out on youtube.