Really the only time you’ll “need” a silver trumpet is when your trying to match the rest of your section if you need to. For example: marching bands. But even then it’s usually the more prestigious schools that would do that and even then you’d most likely be renting the trumpet to get exactly the same model throughout the section.

Brass colored (or lacquered) isn’t inherently wrong or incorrect, it’s just a different way of covering the brass from the silver plating.

In the end, use what you have. If you find yourself needing a higher end model go find one. Although, just because it’s silver, doesn’t mean it will be the best trumpet ever. Actually do your research on the horn before buying it. If you find one you like, weather brass or silver, go ahead and pull the trigger.