Who uses Exchange online protection+Exchange 2016+Exchange 2010?

Question

Microsoft Exchange

Exchange 2010 is becoming obsolete, spam protection in the form of TMG for Exchange will soon lose its relevance. I did not see the point in configuring Exchange 2016 with internal spam filters (as it is already clear from the words of MS that such support will soon leave).
Naturally money for corp. there is no paid solution. There is a way out in the form of a subscription to Exchange online for 5-10 users. When configuring, we specify that all mail be redirected through Exchange online protection. Thus, we get centralized spam protection, and someone from top management will get a box in the cloud.
The question is who uses such a scheme? Yes, and in conjunction with Ecxh 2010 to support a number of clients with the old version of Microsoft Outlook.
What are the pitfalls?
On paper, everything should be beautiful in this scheme. Interesting experience of colleagues. Or will someone else suggest an option?
Thanks in advance!

Answer 1

1. TMG has never been used to protect against spam
2. The whole line of Exchange had a very primitive inefficient set of anti-spam solutions
3. Your anti-spam will work for 5-10 users. The rest of the incoming letters drop, tk. it will probably be necessary to run the wizard for the hybrid (combine onprem and cloud). Although I am not 100% sure of this, my instinct tells me that this is so.
4. Exch2010 + Exch2016 - if this combination is supported by MS, then there should be no problems.

Answer 2

If it's not a secret, how much is a subscription?
ps Always used corporate solutions...