I don't think you would feel an upgrade by going from VSD1 to GR02be. I owned the GR02be for a year, then bought the VSD1, and I kinda regretted that. Not because the VSD1 is bad, but it wasn't the upgrade I hoped it would be. I was pretty disappointed so I got the GR07be only a month after that, baaad for my wallet, but totally worth the upgrade
. Since Vsonic IEMs already have so great value for money, if you want to have an upgrade, you'll have to pay much than that. The GR02be has a V-shape sound signature, colder and cleaner; while VSD1 is fuller and warmer. Bass isn't bloated at all IMO, it has pretty much the same impact with the GR07be, but less details and texture. But noted that the GR02be sound is a lot different than the VSD1, so if you like the VSD1, you might not like the GR02be