For those new to mechwarrior, allow me to provide an introduction.

These are not ultra fast, missile dodging anime style mecha. These are big slow stompy deathbots that will get hit by hundreds of missiles, get annoyed and fire back. Fast kills are rare, instant kills are extremely rare.

A battlemech is a 20-100 ton battle machine. Each section of the mech has it's own independant health, and you can lose most of them without dying. For example, if you are running a standard type engine you can lose both arms, one leg, your left torso and your right torso and still keep fighting.

You get to customize everything. We're not talking putting skins on your guns, we're talking what guns do you want to carry where, how many rounds for each, how many heat sinks to keep the machine from getting to hot? What size engine? How much armor on your left leg, right leg, left arm, right arm, head, left torso, right torso, center torso, left tear torso, right rear torso, center rear torso? - oh yeah, you get to paint everything too if you still care.

Teamwork is the deciding factor in matches, the nature of the machines and how they move and take damage means that even the most skilled player can't overcome a team that abandons them to the enemy. Putting your team in a bad spot will lose the match even if you are better shots than they are. This is chess with more layers of complexity.

Play intergalactic war. There are 10 factions vying for control of the universe, pick one and start claiming entire planets in their name as you fight your way across the galaxy.

Now that you have the basics, here's the details on how this game has been. I joined in closed beta and have been an active player the entire time, including all the massive meltdowns caused by actions of the publisher. These incidents are incrediby public and easy to look up. Yes, they earned a bad rep.
However, the game itself is quite fun. It is not pay to win - the cash only mechs are not inherently better. Different, but not better than the ones you can get for free. If anything this game is only pay not to grind, which is fine.

Honest final recommendation? If you are tired of fast action, actually want to see who is shooting you, and want to actually fight the other guy give this a shot. If you like it, then put in a few bucks for a pack of mechs, skip a ton of grinding and enjoy yourself. Also, join a team. If you don't join a team, you will get constantly stomped in the community warfare mode. Cannot stress this enough - no team, don't join CW.