In the last few years, you would have needed to go through the verification process to update your 61.75 certificate because:
1. cardboard certificates no longer being valid.
2. English Language Profeciency needed to be added for flying outside the USA.
In the next few years, it's likely that you will need to go through the process again because it is likely, but not 100% certain, that your licence number will change when you get an EASA licence.
You will also need to go through the process again if:
1. Your licence number changes for some other reason
2. You move address.
3. Not sure if you'll need to do it if you lose or destroy your certificate, but I think so.
If your purpose in getting it is to fly in the USA, then this is no problem as you can visit the local FSDO and get it all sorted in time without much fuss.
The real problem is if you fly an N reg outside the USA, you might suddenly find that their certificate is no longer valid, and have to make a quick trip to the USA to get it sorted.
Against this there are saving, in not having to do the training and test for the full certificate, and not having to maintain two medicals.
I think the simple rule of thumb is that is you *Need* to be able to fly N reg is Europe, then you really ought to have a full certificate. If you simply want to fly in the USA, then the 61.75 is enough for you.
dp