Will samples remain in flash memory if i remove memory expan

If you remove memory expansion (internal RAM) yes, as it is used as a Temporary volatile RAM, which means that yes, the Samples only reside there while the power is on, and after being loaded from the USB stick.

The Temp RAM is also used as Temporary Memory for Sampling, but again, you need to save the samples, otherwise you will lose them as soon as you power down the G.

why not just back up everything to USB first?

RAM memory has nothing to do with flash memory. Flash memory keeps its contents intact, even if you remove the RAM module altogether. So you can swap your RAM modules and upgrade to 512MBytes without worrying about the internal flash memory.
Well, just in case, you could backup the internal flash memory before upgrading your RAM memory.

OK, thanks for your replies...

...but when it comes to making a backup Im a little confused -
how do I backup all the samples that I have saved in the flash memory, "Save Project" or what ? I really dont understand
the difference between the saving modes in the manual....

Your user samples are saved into projects. The internal memory holds a single project, while you can save several projects in a compatible USB stick.

In order to backup the internal memory you have to insert a USB stick to the "USB memory" port of the Fantom-G and it has to be compatible with the Fantom-G.
First of all, you have to load the internal project by pressing Menu > Project > Load > Internal. Then hit OK and the project will be loaded.
Then you should save this project into USB memory, by pressing Menu > Project > Save as > USB memory. Select a name, hit OK and the Fantom-G will backup the internal project into the USB stick.

Alright ! Now I think Im getting it - I have to do the load thing first to
create a project of the samples before I can save them as one...right ?

I´ll try it tonight, thanks so much for your help !

let me take this fine opportunity to ask this question. I've thought about it plenty of times before, but now seems like a good time to bring it up.

what good is a 16GB flash drive when the most RAM you can have installed is 1GB... what else could someone possibly have on a drive that would take up 15GB more of space...

I just don't really see the need. I have an 8GB, and even at that, I don't know what I could possibly need an 8GB drive for on the FG. I felt like th 8gb was a happy medium between the 16Gb and the 4GB

thanks

Buying a USB stick bigger than 1GB will help fitting more than one project. While the internal memory can hold only project, a USB stick can hold unlimited number of projects. So, the bigger your USB stick is, the more projects you can save and use at a time.