While he is a little bit on the expensive side, and likely to attract removal, it's child's play to use this dragon to gain as many cards as you could possibly need
White and red are pretty equal in terms of numbers, but looking through, I think white offers a little more in terms of differing synergies with Equipment
Usually, they contain a promotional ultra-rare card which many are excited to get, with a variety of booster packs
I'd recommend using resources like TCGPlayer to find the market average, and then try to find listings below that, so you're at least paying cheaper than you might be
That's the lure of gambling. Rips terms of service claim the user experience is different than gambling, but it doesnt shy away from the potential harm caused to users