Profile T2 One-Pay vs. TurboTax Business Incorporated T2 - Canada

I only have to file one T2 corporate income tax return with CRA. Looking at Profile T2 One-Pay vs. TurboTax Business Incorporated T2, the pricing for each is not much different. I expect Profile T2 One-Pay is more robust/comprehensive and was therefore, leaning towards Profile T2 One-Pay unless there are reasons why I should purchase TurboTax Business Incorporated T2. Please let me know why TurboTax Business Incorporated T2 might be a better choice. 

2. Is the Profile T2 One-Pay program identical to Profile T2 available to tax professionals or is the Profile T2 One-Pay program a scaled back version with less features?

3. With Profile T2 One-Pay, I thought I could Efile with a WAC only; someone mentioned I need an Efile number also. Which is correct please?

4. Are the Profile T2 One-Pay and TurboTax Business Incorporated T2 programs both available as download programs (vs web based online programs)?

Thank you for any comments.