They're both great JRPG series. Tales is probably more user friendly to get involved with though for a first time user. You should check out Tales of Vesperia on X360 or Tales of Graces F on PS3 as both can be purchased pretty cheap these days.

Tough choice... for now Persona 5 since Tales Of has a history of ups and downs depending on the fans reaction to the title.

I'm going to say Tales of

Tales. Almost every Tales of title on consoles has sold more in Japan than any version of Persona 3 or 4 sold separately. Except for the 360 version of Vesperia. The ones on consoles that didn't sell as much were less than 100,000 difference.

I'd say persona 5. Tales of Xillia is sitting at about 0.67 million and i can't see it's sequel reaching above that. The original PS2 Person 4 sold about 0.36 million copies according to VGC numbers, but the series has gained quite a lot of popularity since then. Couple that with the several year wait for P5 and it should do very well.