The size thing has been done to death, here's my older thoughts on it:
http://soldatetain.wordpress.com/2013/04/22/perry-desert-rats-on-the-matter-of-size/On the new releases, I think these are directly competitive with Warlord - and frankly, much nicer. Perry have, for me, perfect sculpting and releases. Once they move a little bit later, to NW Europe, I don't know why anyone would buy Warlord. It's just not fair to compare the quality!
Of course, I no longer have a pony in the race; having sold all my 28mm (well, I have a Perry Italian army that I have to list yet), I still think Perry are just superior.
Also, the Blitzkrieg tanks are gorgeous, easier to get to the table, and of flawless quality. Perry are really the front runner.