The Heller "Panzerschiff" kits (they made all 3) are pretty good for their age, among the best of Heller's 1/400 warships. They aren't anywhere near the standard of the new 1/350 Graf Spees from Trumpeter and Academy, but have no major "issues" and are a very good basis for a decent model. I've built their Scheer and have the Lutzow unbuilt, I also had the Graf Spee but sold it when I got the Academy 1/350.

All 3 kits accurately represent the differences between the two ships, IIRC Lutzow is in a late-war fit (converting it to the original "Deutschland" would be a lot of work), Scheer is mid-war and Spee 1939 (River Plate) fit.

Since you got the Tom's PE set with the kit, I'd say build it rather than selling it (the Heller Panzerschiff kits rarely sell for much more than retail on eBay, if that) unless you aren't keen on building in the slightly smaller and now "obsolete" scale of 1/350 - if so, I wouldn't be surprised if Trumpeter produced a 1/350 Lutzow/Deutschland (and Scheer) sooner or later!

One more aftermarket accessory you might find worth buying is Tom's Modelworks "German Naval Doors" set, which will improve the near-featureless appearance of the superstructure bulkheads a lot (a problem with most Heller kits). The Tom's Lutzow-specific PE set doesn't include any doors or hatches.