I would honestly recommend that you buy a few non-magnetic, budget cubes before getting a magnetic one, just to see which road you want to go down.
I'd recommend all of the following 3x3s:
YuXin Little Magic stickerless (US$ 3.65 )
MoYu MF3RS2 stickered black (US$ 5.65 )
QiYi Warrior M (US$ 2.95)
ShengShou GEM (US$ 2.55)
Think of it like a taster pack where you're getting a little bite of everything for under $15. The Little Magic is stickerless, fast and very loose, the MF3RS2 is stickered and solid, the Warrior W is stickerless, textured, loose and buttery and the GEM is stickerless, solid and smooth. Plus, these puzzles will give you the chance to do a bit of lubing and tensioning without fear of messing up a more expensive puzzle and the MF3RS2 and Little Magic are excellent once magnetized, which you can learn how to do yourself sometime down the road.
Many will question the addition of the GEM,but it's a good cube and the tiled exterior can be taken off easily. Color some tiles black with a sharpie and you can make a white-cross training cube very easily. Remove the sharpie from some tiles and you can make an F2L training cube. Get six GEMs together and you can make anything...
It's just an idea.