I think Pozar's book is better in case you don't like a lot of equations, on the other side Collins book is a very good reference in Microwave but it requires good mathematical background.
both books are excellent! Pozar's book is more suitable for beginners, Collin's is a good preparation for advanced, in-depth study. However, both books give you just background theory necssary to understand practical issues.
Pozar is very widely used in Universities and as you can see most people
like his book better. I would add that G. Gonzales has a very good book
for Microwave Design, you might want to check it out also.
Pozar's pretty easy to absorb but quite costly. Colin's on the other hand, contains much more information and is a real bargain. If you've got the cash, get both of them.....
Some topics are covered better at Pozar while some others are better at Collin .Amplifiers for exaple are discussed in much more detail at Collin than Pozar while filters on the other hand are of more circuit implementations at Pozar .