SMP vs TYRO vs. Banks

I would like to know the comparitive advantages of SMP, vs TYRO vs. the Banks.
And what would switch a customer over from one to the next.

My experience with banking relationships is that the are very sticky.
It is painful to move transactional Business Banking to another provider... The finance team all grumble about how much work it is. Suppliers pay to the old accounts etc. So there needs to be a good reason to do (significant cost advantage, or the current bank really lets you down).

I suspect switching terminals is easier. Though many merchants probably prefer that it is integrated into their own POS software (so that the sale doesn't need to be entered in manually). But most contracts are month to month, so switching is easy. However, I have very limited experience with any of them, so can anyone comment on the qualitative factors at play with SMP etc?

I am pretty tight, so I would think that for a fairly commoditised service like merchant fees, you just want the provider with the best rates?
But then again, more and more merchants are switching to surcharging for CC and Debit card payments (to pass these back to the customer). I have noticed this more and more, and not always with signage that warns you of this. If that is the pervading trend, then a merchant might not care if it was 1.5% or 1.0% transaction fee (which would otherwise be material difference on profit margin in some industries).

I have observed that the banks are generally able to offer better rates on terminals (for medium sized customers). Yet it would seem that Tyro and SMP are still cutting their lunch. I assume this is on the back of better customer service and support, whereas dealing with a large bank and their 1300 numbers can be a bit of a run around.

And most important there is the race between TYRO and SMP. David and Goliath in terms of market cap and revenue.
I would appreciate any thoughts from HC members with experience in this space.
Thanks