They will promise you a role, have you sign a contract and put you through the paperwork phase all to pull the role at last minute. They are NOT on your side as a contractor.
Timely salary, and the team is good with keeping in touch with contractor.
Cons
You have to negotiate properly, they will not budge later.
No other perks worthwhile. The 401k is around 1.5% match. Don't know how medical is as I was covered through spouse
For long term contracts, you better negotiate with PTO and periodic increments while interviewing