Narrow it down some.
What are you really looking for? Pay, location, hours? Family, have a perm home, looking for a perm home?
Read everything you can; here and the other boards/blogs out there. There is good and bad in every post, message, article; you will be able to tell.
"Pantravelers.org" is a pretty good site, free subscription for most of the info, paid subscription for the rest. Of course you know about "Allnurses.com", I have read through just over half of the posts on the travelers section.
To your questions then. Travel companies will have different benefits that may or may not fit what you need. "Highwayhypodermics.com has a company review posting which will get you a good feel for what you might get from the "company".
Ultimate List Of Travel Companies And Their Benefits!
Travel Company Evaluations
I took those lists and started from the top, even some of best companies just did not fit what I was looking for, and just to be contrary I have been working with CCTC (not well liked here) and have been pleased (they can get you in to hospitals others can not).
Recruiters are a different story. You should be talking to 3-4 different companies, and so, 3-4 different recruiters. They are looking for a paycheck and should be working to place you. If they aren't placing you there are probably 2 things going on 1) they are not working hard enough or 2) you are missing some skill set/certification that is needed. If it is #1 get rid of them nicely and move on. If it is #2 your recruiter should know and should have told you. If they do know and they have not told you see #1 above.
You will have a tough time having someone recommend a travel company for you, a lot of variables (see above) and it is kind of frowned upon. Once you get 15 posts you can send a PM and if asked you will get a lot of responses.
More about you. How many companies have you tried? What is your specialty? How long have you been a nurse? Where are you looking, state, location? What are your must haves?
I'll keep an eye on this post and help out when able.