I have a couple of metal Grendels (second hand from a lot), so I have some experience with them, and in mine opinion they are Meh in performance (compared to other Clan omnis) and have a forgettable appearance, like the last kid that gets chosen in gym class. Poor Mech, it even gets bullied by Clan Light Mechs.....
Not my experience with them. They have problems facing off against mechs in their mobility tier, and can have trouble earning their points back, but those are hardly unique problems for mechs in this box. But if you want a flanker that the enemy will have a heck of a time killing and with enough firepower it can't be ignored? hard to do better. In almost all ways it compares favourably with the shadow cat. It does better the bigger playing area it has access to, like a lot of fast, longer-range mechs.
Solid alternate configs. I'd like more pulse lasers on a natural jumper like this, but it is entirely understandable why it didn't get them.
[Edit] - My glitch is with the Adder. It pays full BPV for a second PPC it can
occasionally use, at a cost for your next turn's mobility (Great cost if you ran)
Not a beginner mech. In fact, it's on a par with the worst of the succession wars for the skill it requires.