S7 1200 and distributed peripherals. What are the pitfalls?

Question

Siemens

We are currently using several moxa iologic 1214 and Siemens Logo kits!
Using modbus TCP, we send data to moxas, from there the logo takes them, plus it reads the sensors and does its part of the work. And so at each point separately.

There was an idea to replace all this stuff with one S7-1200 and a pack of ET 200SP with I / O modules (IM155-6PN Basic). Connect by profile. Send/receive all data directly in 1200. There is no experience with 1200, there is a little (self) learning.

The question is - what restrictions, pitfalls, pluses and minuses can I catch?
At each point within 10-15 I / O pins, according to a rough estimate, the price tag of the 200SP in this configuration turns out to be similar and even slightly lower.