For Canadian investors and business owners: BDC vs big 5 banks?

I am In the in the process of financing an offer to acquire a business in Canada and I wonder why BDC is often the choice for business searchers as I was told.

BDC has prime rate of 9.05%, vs other big five banks at around 6.95%. I was offered by BDC at a rate of prime + 5.5%, vs prime +2% from big five commercial banks. That is 14.55% vs 7.95% rate difference. BDC does not put lien on the personal house but they do require personal guarantee as well. BDC requires review engagement report for any loan over 350K but other big fives don't.

I would appreciate some feedbacks from Canadian searchers and business owners. Thank you!