I heard good stuff about paradise, but everything I've heard about serious is good. Attitude seems like the place, I actually flew all the way to Amsterdam.... spent like $2000 just to get there and back.... but had a damn good time (it was like my 20th time, but I hadn't been back in 9 years.
If you have limited funds, don't mess around and get something from serious... you'll be happy. I've also been really tempted by the Cheese and derivatives... get some of that also if you want to experiment.
The only thing I would say about white berry is that it is single cola dominant... check wiht more experienced growers, but I don't think single cola plants like topping and don't benefit as much from LST (fancy way to say tying down). I have 3 strains going... and one is really cool because it has 2 main stems (from topping) and lots of side branches and buds reacting to tying down.
I have a small space and wanted to maximize surface area near my lights anyways so I tied my plants down so that even though they are probably 2-3 feet tall, none of them reach more than 12 inches from the pots. I'll post pics to help you out, I just got my camera back though and have no memory card in it.
If you have the cash I'm sure that Paradise is worth the money (but if you're like me you will always wonder if you got the best out there), I'm just pushing Serious on you because it's been highly recommended to me. If you have the cash and want good quality... get something from Serious, something from Paradise, and I'd even take a risk on the 3rd strain from someone else (just not greenhouse from what I've heard). You are guaranteed to get quality product from Serious, Paradise, TH Seeds, and some other companies.... but if you want the best of the best you'll be racking your brains forever.
I am actually planning on growing out some hybrids crossed by a friend next (as long as they get here), but my next purchase will be White Russian and Kali Mist form Serious, Cannalope Haze from DNA (just cause it looks so good and Hazes are supposed to be the bomb), and I'm gonna take a shot at something from DJ Short (gotta get that from a place like "hemp depot"- seems shadier than Attitude, but WTF... I've got the cash).
Good luck, and just get something. You'll be happy as long as you stick to the quality breeders.
Is it really worth paying so much more for the same strain from one breeder/brand over another? In your opinion, who's worth paying the big bucks to?