Hi!

premium come often?if we win a real object we can receive in othe country than Germany?

I can't tell you the exact drop rates unfortunately, but I think premium drops are rather rare.
As far as I know they restrict packs with real physical objects to German speaking countries and other packs are also not available worldwide. I wouldn't recommend to use a VPN since it can get you banned and you probably wouldn't be able to redeem the won code anyway.

from your experience do you think that we win better things if we buy SS by pack (5 or 10) than solo (with diamond not money)

Lootboy seems to often post promotions on social media where they promise you a specific drop if you buy 10 packs at once...so that may be something, but there's always the risk of getting banned or losing them because of technical problems (some people reported such cases, so I think a lot of people switched to redeem diamonds right away), but in the end it's your decisision.

do you think we can win more steam card at the beginning or at the end of month (I need one for don't have steam limited account XD)

I haven't found a pattern in that unfortunately xD But let me know if you find something out :P

I hope that helps :)
Have a nice day!

Thanks! Accepted :)