My take and experience on the "modelling" mics is that they offer a wide palette of "simulated" flavours. A good analogy is flavoured potato chips. They all start with a rather neutral tasting chip and add a simulated flavour. They taste "like" the flavour added, but will never have the nuance of a proper combination of the two real foods (potatoes + dill, as an example) mixed and cooked together.
You really do need to try before you buy. I'm not sure you will hear a world of difference between the TLM103 and MK4. You will hear a big difference, and have flexibility of choice, if you add different types of mic to your collection (shotgun, ribbon, dynamic, etc.). As an example, you can buy a Shure SM7B (dynamic) and a Rode NTR (ribbon) for almost the same price as a single TLM103.
If you are fixed on getting one mic for all situations it is even more important to do a proper audition of mics you think will be the right choice.