RAM

what is the benefit of upgrading from the standard 16mb RAM to 128mb RAM...will it really help with production?

Each person will give you different answer, because it's only up to you and style of production that you are using.
128 mb of memory gives you a looot of sampling time, but on 16 mb you can sample a lot too.Take a look at sp 1200 and sampling time on this machine Some people can still use only this 1 piece of equipment and create a dope song/beat by chopping everything into little pieces and sampling at high speed, then pitching it down in the unit to save up sampling time.

I use 2000 xl model and I have 32 mb of memory, but I think that I never go further than 10 mb alltogether in one project.

Conclusion - in my opinion it won't do much for you, to help with production. Learn some basic skills (maybe you already have them), and sample. If you notice that 16 mb isn't enough, cop the 128 mb and go crazy

have fun