Ring Sizing Reccomendations?

[LinSF]

I need to decide on a ring size for my engagement ring, and am having a hard time trying to figure out what will work. I have some plastic sizers I have been trying on at different times of the day. In the evening I am a size 5 (goes on easily, 2-3 second tug over knuckles to come off), but if I leave the sizer on overnight I can't get it back off my knuckle in the morning. 5.5 is loose in the eve, and then I also have to tug a little to get it off in the morning if I sleep with it on.

The shank on my ring will be 2mm, and ultimately I will likely wear a spacer band of 1.8-2mm and an eternity band of about 2.5 mm. I can't go larger than 5.5 because that's way too loose in the eve, but also need to consider the final stack. Do you think 5.25 would work or should I go for the 5.5?

Also, I am measuring at a cooler time of the year and my fingers may swell with heat. But I have no idea what that would do! I know the ring can be adjusted, but I hate being without my rings!

 

[PintoBean]

Go bigger and buy a plastic noodle or add sizing beads for now. I'm concerned about summer and potential swelling.

Also, if you stack rings, you'll need to size up a little too.

 

[EC8]

My recommendation is to go slightly larger (5.25) especially If you are planning on wearing up to 3 rings at a time. You may want to try wearing 3 sizers at the same time to see how they work. I would suggest the eternity to be the largest size (5.5) you can always wear it the furthest from the knuckle if it gets too loose.
Lastly, You may want to provide the vendor with the plastic sizers you end up using. I have found variations between different sizers & mandrels; the vendor can measure what you give them on their mandrel to ensure the right size/fit.