When it comes to going through a company school vs. a private then having your tuition reimbursed, I'd go private every time, with the one exception mentioned above, Watkins Shepard.
The biggest problem with the company schools is that if you don't stay on with them for your first year you then owe them the whole amount of the school, typically $3-4k, even if you stayed on for 360 days. Read the fine print VERY carefully and make sure you understand the contract completely before signing. Another reason I mention Watkins is because they don't do this. The help repay the cost of school(even their own school) and if you quit before it is paid for you just owe the remainder of the balance, not the whole amount.
The other problem with company schools is that they just teach you about driving for them, private school are more inclined to teach you how to survive in the industry as a whole and not just one company. If you have been laid off look to see if the state has any re-training programs, the private schools use these a lot and can point you in the right direction. Washington State paid for my private school($4k) through one of these programs because I had been laid off due to NAFTA.
Pre-hires don't mean anything. If you meet the minimum requirements any company will give you a pre-hire status. When you get to orientation you will have to re-submit the application all over again. All you references and time off MUST check out(5 year history for the fed rules) or you will be sent home and they will NOT pay for the ride back home. This is standard practice in the industry, very few companies will do all the legwork to make sure you are hire-able before you get on the bus for orientation. It is a good idea for you to go ahead and call to make sure all your references check out before getting on the bus.
Pull a 5-year copy of your driving record too and keep it on file. Ask for the complete record for employment, it will have the most info on it.
I personally haven't worked at CR and don't know anybody who has. A good place to check for company specific info is The Truckers Report. There is a TON of info there for most major companies, most is first hand experiences. Again, I'd look into Watkins Shepard while you are digging around on that site.
FYI, I am NOT affiliated with Watkins in any way. I haven't worked for them, I haven't applied or anything. I have talked to a LOT of their drivers and they all love the company and say the training was fantastic and they felt fully prepared to go out on the road by themselves at the end of the training.
I'll have more later, got a deliver to make...