mmm, i'm gonna tell u my own experience if it helps u, would be great.. I was born in Argentina, and at the age of 20 i moved to Spain, and i had been living in Spain for almost 8 years. And at the beginning ppl didnt understand me that well, even if we speak the same Language, they are quite different. So at that time, i had decided to reorganise my own language, soon i ended up speaking in the same way as Spanish ppl do, i can say that for me, it was a need, as i can tell u, based on my experience that many many Spanish ppl dont understand if they are spoken in a different way, Some do know languages variatios due to mass media, but many others dont. so my mate, from my experience, i would recommend to u, that it would be better if u learn how Spanish is spoken in Spain, or wherever u go, learn the use of the language.

Si Zhang, te entenderán seguro.Nosotros decimos 'ustedes' ( formal) o 'vosotros' (informal), si estas en España de turismo y hablas con las personas allí, ellos se dirigirán a ti con la forma 'usted' porque es mas respetuoso.

No te preocupes. Los españoles pueden entender

I live in Spain and I use "ustedes" instead of "vosotros", since that's how my dialect works. I've been to the Spanish Mainland and I talk to Mainland Spanish people often (where they use "vosotros") and I've always used "ustedes". Some might be confused because they're not used to it and might even ask you to be less formal (since that's what they consider formal), but once you tell them it's because you speak Latin American Spanish and that ustedes is the same as vosotros there, they'll understand. There's no need to learn "vosotros"; the verbs are way too complicated and unnecessary. You'll have no problem if you use "ustedes"!

Te entenderán perfectamente :D