I have never been into either author, but I might have given Martin a try if I had a complete series to look forward to. There are exceptions, but I generally don't start a series until I know the final book is published or at least in the can. William Gibson and Justin Cronin are my two exceptions...I will read a new Gibson the moment it appears, and The Passage was just too compelling to pass up. (My biggest problem is that I re-read the earlier books in a series to catch up...so in the case of Cronin, I've read The Passage three times, The Twelve twice, City of Mirrors once...you get the picture.)